Methods for inhibiting the transmission of HIV using topically applied substituted 6-benzyl-4- oxopyrimidines

ABSTRACT

A method for inhibiting sexual transmission of HIV comprising topically applying to the skin or epithelial tissue of a human a composition comprising a non-nucleoside reverse transcriptase inhibitor (“NNRTI”) that is able to inhibit viral replication for periods exceeding 12, 24, or even 36 days, at concentrations below even 10 μM. In one embodiment the NNRTI is a dihydro-alkyloxy-benzyl-oxopyrimidine (DABO).

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to provisional application serial No. 60/249,532, filed Nov. 17, 2000.

FIELD OF THE INVENTION

[0002] The present invention is compounds, methods, compositions, and devices for preventing infection by sexually transmitted HIV.

BACKGROUND OF THE INVENTION

[0003] The retrovirus designated human immunodeficiency virus (HIV) is the etiological agent of the complex disease that includes progressive destruction of the immune system (acquired immune deficiency syndrome; AIDS) and degeneration of the central and peripheral nervous system. Since it emerged as a public health threat in the early 1980's, efforts to control or eradicate the disease have focused principally on options for treating the disease after an individual has already become infected.

[0004] The use of condoms provides a substantial degree of protection against transmission of HIV infections during sexual intercourse. However, the use of condoms is not 100% effective against the transmission of HIV. Moreover, couples often do not use condoms. A topical composition that could be inserted into the vagina or rectum by a foam, gel, sponge or other form, or which could be topically applied to the male genitalia, would in many cases be preferred over condoms. Moreover, the prophylactic effectiveness of condoms could be improved by including a suitable microbicide in the lubricant coated on the exterior of the condom. However, to date little progress has been made to develop an effective topical composition against the transmission of HIV.

[0005] Most work to develop topical HIV prophylactic compositions has focused on the use of surfactants and buffers, such as the over-the-counter product nonoxynol-9. Surfactants and detergents disrupt microbial and sperm membranes by lysis and emulsification. Surfactant-containing creams and gels have the advantage of being very broad in their killing ability, and thus can kill the HIV virus and viruses associated with other sexually transmitted diseases. The use of surfactants and buffers is, however, substantially limited by the damage they can cause to cell membranes. In the vagina, nonoxynol-9 has been shown to thin vaginal walls. In the rectum, nonoxynol-9 can cause rectum walls to slough off.

[0006] Other virusidal compositions being investigated for use as HIV virusides include carageenan and other large sulfated polysaccharides that stick to viral envelopes and possibly shield cell membranes. Philips D M, “Of Mice and Men—Assaying Vaginal Virusides,” Virusides 2000, Mar. 13-16, 2000, Alexandria Va., page 12, abstract A20. Monoclonal antibodies have also been proposed as HIV prophylactics, and some antibodies have shown a promising degree of protection. (Mascola J et al., “Role of IgG Antibody in Protection against Vaginal Transmission of an HIV-1/SIV Chimeric Virus,” Virusides 2000, Mar. 13-16, 2000, Alexandria Va., page 7, abstract A10; Watanabe, M., Boyson, J. E., Lord, C. I. and Letvin, N. L. “Chimpanzees Immunized with Recombinant Soluble CD4 Develop Anti-self CD4 Antibody Responses with Anti-human Immunodeficiency Virus Activity”, Proc. Natl. Acad. Sci. U.S.A., 89, 5103-5107 (1992); and Perno, C. -F., Baseler, M. W., Broder, S. and Yarchoan, R., “Infection of Monocytes by Human Immunodeficiency Virus Type 1 Blocked by Inhibitors of CD4-gp120 Binding, Even in the Presence of Enhancing Antibodies”, J. Exp. Med., 171, 1043-1056 (1990)).

[0007] International application published as WO 00/03998 to P. LaColla and M. Artico disclosed substituted 6-benzyl-4-oxopyrimidines useful in the treatment of HIV.

[0008] Elise A. Sudbeck, Chen Mao, Rakesh Vig, T. K. Venkatachalam, Lisa Tuel-Ahlgren, and Fatih M. Uckun disclose various dihydroalkoxybenzyloxopyrimidine derivatives shown to be effective against HIV, which were designed based on structure analysis of potent normucleoside inhibitors of the human immunodeficiency virus reverse transcriptase.

[0009] Scientists have recently reported several biological discoveries that improve our understanding of how HIV enters an organism following sexual contact, which could lead to prophylactic substances that interfere with HIV's interaction with its target cells. These discoveries revolve generally around T lymphocytes, monocytes/macrophages and dendritic cells, suggesting that CD4 cell receptors are engaged in the process of virus transmission (Parr, M. B. and Parr, E. L., “Langerhans Cells and T lymphocyte Subsets in the Murine Vagina and Cervix”, Biology of Reproduction, 44, 491-498 (1991); Pope, M. et al., “Conjugates of Dendritic Cells and Memory T Lymphocytes from Skin Facilitate Productive Infection With HIV-1”, Cell, 78, 389-398 (1994); and Wira, C. R. and Rossoll, R. M., “Antigen-presenting Cells in the Female Reproductive Tract: Influence of Sex Hormones on Antigen Presentation in the Vagin a”, Immunology, 84, 505-508 (1995)). Geijtenbeek TBH et al., for example, recently reported that HIV tightly binds the DC-SIGN molecule on the surface of dendritic cells, through the gp120 HIV envelope protein. When the dendritic cells present microbial antigens to CD4+ T helper cells to stimulate an immune response, the dendritic cell inadvertently transfers the HIV to the CD4+ T cells, thereby advancing the progression of the infection.

[0010] Some have postulated, based upon these discoveries, that prophylactics can be designed that block the interaction between DC-SIGN and gp120. Similarly, DC4 and chemokine receptor blockers could be designed and administered to prevent the transfer of HIV from the dendritic cells to the CD4+ T cells. However, methods that rely on the specific interaction of HIV and human cells are limited, because the infection pathway has not been fully defined and may be diverse. (Miller, C. J. et al., “Genital Mucosal Transmission of Simian Immunodeficiency Virus: Animal Model for Heterosexual Transmission of Human Immunodeficiency Virus”, J. Virol., 63, 4277-4284 (1989); Phillips, D. M. and Bourinbaiar, A. S., “Mechanism of HIV Spread from Lymphocytes to Epithelia”, Virology, 186, 261-273 (1992); Phillips, D. M., Tan, X., Pearce-Pratt, R. and Zacharopoulos, V. R., “An Assay for HIV Infection of Cultured Human Cervix-derived Cells”, J. Virol. Methods, 52, 1-13 (1995); Ho, J. L. et al., “Neutrophils from Human Immunodeficiency Virus (HIV)-SeronegatiVe Donors Induce HIV Replication from HIV-infected Patients Mononuclear Cells and Cell lines”: An In Vitro Model of HIV Transmission Facilitated by Chlamydia Trachomatis., “J. Exp. Med., 181, 1493-1505 (1995); and Braathen, L. R. & Mork, C. in “HIV infection of Skin Langerhans Cells”, In: Skin Langerhans (dendritic) cells in virus infections and AIDS (ed. Becker, Y.) 131-139 (Kluwer Academic Publishers, Boston, (1991)).

[0011] Efforts by researchers to develop an HIV vaccine have also not yet been successful. Siegel et al. reported that vaccination with inactivated SIV did not protect African Green monkeys against infection with the homologous virus notwithstanding a strong immune response to SIV. (Siegel, F., Kurth, R., and Norley, S., (1995), “Neither Whole Inactivated Virus Immunogen nor Passive Immunoglobulin Transfer Protects Against SIV Infection in the African Green Monkey Natural Host”, J. AIDS, 8, 217-226).

[0012] Therefore, there remains a need for an effective topical prophylactic against the sexual transmission of HIV. It is an object of the invention, therefore, to provide topical prophylactic compositions against the sexual transmission of HIV, methods for using such compositions, and devices that deliver such compositions.

[0013] It is another object of the invention to provide compounds that have extended activity against the HIV virus.

[0014] It is another object of this invention to provide a topical composition that can be applied to the areas of skin and mucus epithelia at highest risk for exchanging HIV pathogens. Formulations of such compositions can be based upon existing topical compositions used as lubricants and contraceptives, which are often present as lotions or gels, or coated to the exterior of condoms.

[0015] It is another object of this invention to create new, long-term prophylactic methods for women based upon existing contraceptive devices, including sustained release devices to be inserted in the vagina (intra-vaginal devices such as sponges and cervical caps).

[0016] It is still another object of this invention to provide suppositories and intra-vaginal or rectal pills that can be inserted into the vagina or rectum in order to release one or more anti-HIV agents at a predetermined rate.

[0017] Yet another object of the invention is to deliver, along with the anti-HIV agent, agents against other things from which the user desires protection, such as sperm, toxins, and/or STD pathogens.

SUMMARY OF THE INVENTION

[0018] The invention provides compounds, compositions and methods for prophylactically inhibiting the spread of AIDS. The compounds of the present invention display inhibition of HIV replication, and do so for a prolonged period of time, which renders them useful in prophylactic applications, wherein the frequency or duration of use are not always predictable. The compounds are also useful in prophylactic applications because they inhibit the HIV virus upon contact at very low concentrations, before the virus has infected its host and begun replication. Non-nucleoside reverse transcriptase inhibitors (“NNRTI”) have proven especially invaluable in this type of application.

[0019] Thus, in one embodiment, the invention provides a method for inhibiting sexual transmission of HIV comprising topically applying to the skin or epithelial tissue of a human a composition comprising a non-nucleoside reverse transcriptase inhibitor (“NNRTI”) that is able to inhibit viral replication for periods exceeding 12, 24 or even 36 days, at concentrations below even 10 μM.

[0020] In one embodiment the NNRTI is a dihydro-alkyloxy-benzyl-oxopyrimidine (DABO). This class of compounds is capable of inhibiting HIV multiplication targeting reverse transcriptase without bioactivation. Preferred DABOs include compounds of formula (A):

[0021] as herein defined.

[0022] In another embodiment the invention provides a topical composition in the form of a cream, lotion, gel, or foam, comprising a dihydro-alkyloxy-benzyl-oxopyrimidine.

[0023] In still another embodiment the invention provides a composition in the form of an intra-vaginal or intra-rectal pill or suppository comprising a dihydro-alkyloxy-benzyl-oxopyrimidine.

[0024] A still further embodiment provides a device for inhibiting the sexual transmission of HIV comprising: (a) a barrier structure for insertion into the vaginal cavity, and (b) a composition comprising a dihydro-alkyloxy-benzyl-oxopyrimidine.

[0025] Still a further embodiment provides dihydro-alkyloxy-benzyl-oxopyrimidines defined by the foregoing structure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026]FIG. 1 is a three dimensional line graph showing the levels of viral p24 in cell culture supernatants treated with the specified concentrations of MC 1220.

[0027]FIG. 2 is a three dimensional line graph showing the levels of viral p24 in cell culture supernatants treated with the specified concentrations of Nevirapine.

[0028]FIG. 3 is a three dimensional line graph showing the levels of viral p24 in cell culture supernatants treated with the specified concentrations of MC-1047.

DETAILED DISCUSSION OF THE INVENTION

[0029] In one aspect the invention provides a composition and method for inhibiting sexual transmission of HIV comprising topically applying to the skin or epithelial tissue of a human a composition comprising a non-nucleoside reverse transcriptase inhibitor (“NNRTI”) that is able to inhibit viral replication for periods exceeding 12, 24, or even 36 days. In separate embodiments, the composition is able to inhibit viral replication for such prolonged periods at concentrations as low as 50, 35, 20, 10 or 5 μM. The ability of a compound to inhibit viral replication is preferably evaluated by the HIV-1 p24 antigen enzyme-linked immunosorbent assay. Suitable ELISA kits are available, for example, from Abbott Laboratories. Particular methods for their use are set forth in the examples herein. The ability of a non-nucleotide compound to inhibit reverse transcriptase can also be assessed by the methods set forth in the examples hereof.

[0030] The composition is preferably applied topically to any skin or epithelial tissue that comes in contact with bodily fluids of a sexual partner during sexual intercourse or foreplay, including the vaginal endothelium, the rectal endothelium or the male genitalia. As used herein, the term “topical application” refers to something that is applied to and spread across the surface of the skin or a mucous membrane (by contrast, “systemic” administration refers to a drug or other compound that is ingested orally or injected beneath the skin). A condom lubricant or other genital lubricant is a topical agent as that term is used herein.

[0031] In one particular embodiment the NNRTI is a dihydro-alkyloxy-benzyl-oxopyrimidine, as defined further herein.

[0032] Preferred compositions can take several forms. Thus, in one embodiment the composition is in the form of a cream, lotion, gel, or foam that is applied to the affected skin or epithelial cavity, and preferably spread over the entire skin or epithelial surface which is at risk of contact with bodily fluids. Such formulations, which are suitable for vaginal or rectal administration, may be present as aqueous or oily suspensions, solutions or emulsions (liquid formulations) containing in addition to the active ingredient, such carriers as are known in the art to be appropriate. For “stand-alone” lubricants (i.e., lubricants that are not pre-packaged with condoms), gels and similar aqueous formulations are generally preferred, for various reasons (both scientific and economic) known to those skilled in the art. These formulations are useful to protect not only against sexual transmission of HIV, but also to prevent infection of a baby during passage through the birth canal. Thus the vaginal administration can take place prior to sexual intercourse, during sexual intercourse, and immediately prior to childbirth.

[0033] One method of applying an anti-viral lubricant to the genitals, for the purposes disclosed herein, involves removing a small quantity (such as a teaspoon, or several milliliters) of a gel, cream, ointment, emulsion, or similar formulation from a plastic or metallic tube, jar, or similar container, or from a sealed plastic, metallic or other packet containing a single dose of such composition, and spreading the composition across the surface of the penis immediately before intercourse. Alternate methods of emplacement include: (1) spreading the composition upon accessible surfaces inside the vagina or rectum shortly before intercourse; and (2) emplacing a condom, diaphragm, or similar device, which has already been coated or otherwise contacted with an anti-viral lubricant, upon the penis or inside the vagina. In a preferred embodiment, any of these methods of spreading an anti-viral lubricant across the surfaces of the genitals causes the lubricant to coat and remain in contact with the genital and epithelial surfaces throughout intercourse.

[0034] In one embodiment the compositions are used in conjunction with condoms, to enhance the risk-reducing effectiveness of condoms and provide maximum protection for users. The composition can either be coated onto condoms during manufacture, and enclosed within conventional watertight plastic or foil packages that contain one condom per package, or it can be manually applied by a user to either the inside or the outside of a condom, immediately before use.

[0035] As used herein, “condom” refers to a barrier device which is used to provide a watertight physical barrier between male and female genitalia during sexual intercourse, and which is removed after intercourse. This term includes conventional condoms that cover the penis; it also includes so-called “female condoms” which are inserted into the vaginal cavity prior to intercourse. The term “condom” does not include diaphragms, cervical caps or other barrier devices that cover only a portion of the epithelial membranes inside the vaginal cavity. Preferably, condoms should be made of latex or a synthetic plastic material such as polyurethane, since these provide a high degree of protection against viruses.

[0036] In another embodiment the composition is in the form of an intra-vaginal pill, an intra-rectal pill, or a suppository. The suppository or pill should be inserted into the vaginal or rectal cavity in a manner that permits the suppository or pill, as it dissolves or erodes, to coat the vaginal or rectal walls with a prophylactic layer of the anti-HIV agent.

[0037] In still another embodiment the composition is topically applied by release from an intravaginal device. Devices such as vaginal rings, vaginal sponges, diaphrams, cervical caps, female condoms, and the like can be readily adapted to release the composition into the vaginal cavity after insertion.

[0038] Compositions used in the methods of this invention may also comprise other active agents, such as another agent to prevent HIV infection, and agents that protect individuals from conception and other sexually transmitted diseases. Thus, in another embodiment the compositions used in this invention further comprise a second anti-HIV agent, a virucide effective against viral infections other than HIV, and/or a spermicide.

[0039] In one particular embodiment, the composition contains nonoxynol, a widely-used spermicidal surfactant. The resulting composition could be regarded as a “bi-functional” composition, since it would have two active agents that provide two different desired functions, in a relatively inert carrier liquid; the nonoxynol would provide a spermicidal contraceptive agent, and the DABO would provide anti-viral properties. The nonoxynol is likely to cause some level of irritation, in at least some users; this is a regrettable but is a well-known side effect of spermicidal surfactants such as nonoxynol and octoxynol, which attack and destroy the lipid bilayer membranes that surround sperm cells and other mammalian cells.

[0040] The compositions used in this invention may also contain a lubricant that facilitates application of the composition to the desired areas of skin and epithelial tissue, and reduces friction during sexual intercourse. In the case of a pill or suppository, the lubricant can be applied to the exterior of the dosage form to facilitate insertion.

[0041] In still another embodiment the invention provides a device for inhibiting the sexual transmission of HIV comprising (a) a barrier structure for insertion into the vaginal cavity, and (b) a composition comprising a dihydro-alkyloxy-benzyl-oxopyrimidine. As mentioned above, preferred devices which act as barrier structures, and which can be adapted to apply anti-HIV agent, include the vaginal sponge, diaphram, cervical cap, or condom (male or female).

[0042] The methods, compositions and devices of this invention can be adapted generally to release active agent in a time sensitive manner that best corresponds to the timing of sexual activity. When topically applied as a lotion or gel, the compositions are preferably applied immediately prior to sexual activity. Other modes of application, such as devices and suppositories, can be designed to release active agent over a prolonged period of time, at a predetermined rate, depending upon the needs of the consumer.

[0043] Dihydro-alkyloxy-benzyl-oxopyrimidines

[0044] The dihydro-alkyloxy-benzyl-oxopyrimidines of this invention are preferably defined by formula A described below, combinations thereof, or pharmaceutically acceptable salts thereof:

[0045] A principle embodiment is defined wherein:

[0046] X is —O, —CH₂, —CHK¹ (wherein K¹ is —H, —C₁₋₄ alkyl, —C₃₋₆Cycloalkyl), —S, —NK² (wherein K² is —H, —C₁₋₄alkyl, —C₃₋₆cycloalkyl, or a bond when X—R is nitro), -aryl, or -arylalkyl;

[0047] R is —H, —C₁₋₄alkyl (optionally containing one or more of heteroatoms selected from O, S, and N), —C₃₋₆ cycloalkyl (optionally containing one or more of heteroatoms selected from O, S, N), -aryl, -arylakl, heterocycle, oxo, thio, or a primary amine;

[0048] Y is —H, —C₁₋₄alkyl or —C₃₋₆cycloalkyl;

[0049] Z is —H, —C₁₋₄alkyl or —C₃₋₆cycloalkyl;

[0050] R¹ is —H, —C₁₋₁₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, aryl), or —SW (wherein W is —H, —CH₃, -aryl);

[0051] R² is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW (wherein W is —H, —CH₃, -aryl);

[0052] R³ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW (wherein W is —H, —CH₃, -aryl);

[0053] R⁴ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW (wherein W is —H, —CH₃,-aryl); and

[0054] R⁵ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl), or —SW (wherein W is —H, —CH₃, -aryl).

[0055] A first principal class of 13 subembodiments are defined when:

[0056] 1. Y is —C₁₋₄alkyl, Z is —C₁₋₄alkyl, and X, R, R¹, R², R³, R⁴ and R⁵ are as defined above in the principal embodiment;

[0057] 2. Y is methyl, Z is methyl, and X, R, R¹, R², R³, R⁴ and R⁵ are as defined above in the principal embodiment;

[0058] 3. R¹ and R⁵ are halogen, and Y, Z, X, R, R², R³ and R⁴ are as defined above in the principal embodiment;

[0059] 4. R¹ and R⁵ are fluorine, and Y, Z, X, R, R², R³ and R⁴ are as defined above in the principal embodiment;

[0060] 5. R², R³ and R⁴ are hydrogen, and Y, Z, X, R, R¹ and R⁵ are as defined above in the principal embodiment;

[0061] 6. Y is —C₁₋₄alkyl, Z is —C₁₋₄alkyl, R¹ and R⁵ are halogen, and X, R, R², R³ and R⁴ are as defined above in the principal embodiment;

[0062] 7. Y is methyl, Z is methyl, R¹ and R⁵ are fluorine, and X, R, R², R³ and R⁴ are as defined above in the principal embodiment;

[0063] 8. Y is —C₁₋₄alkyl, Z is —C₁₋₄alkyl, R², R³ and R⁴ are hydrogen, and X, R, R¹ and R⁵ are as defined above in the principal embodiment;

[0064] 9. Y is methyl, Z is methyl, R², R³ and R⁴ are hydrogen, and X, R, R¹ and R⁵ are as defined above in the principal embodiment;

[0065] 10. R¹ and R⁵ are halogen, R², R³ and R⁴ are hydrogen, and X, R, Y and Z are as defined above in the principal embodiment;

[0066] 11. R¹ and R⁵ are fluorine, R², R³ and R⁴ are hydrogen, and X, R, Y and Z are as defined above in the principal embodiment;

[0067] 12. Y is —C₁₋₄alkyl, Z is —C₁₋₄alkyl, R¹ and R⁵ are halogen, R², R³ and R⁴ are hydrogen, and X and R are as defined above in the principal embodiment; and

[0068] 13. Y is methyl, Z is methyl, R¹ and R⁵ are fluorine, R², R³ and R⁴ are hydrogen, and X and R are as defined above in the principal embodiment.

[0069] A second principal class of subembodiments are defined when:

[0070] 1. —X is NK, and Y, Z, R, R¹, R², R³, R⁴ and R⁵ are as defined in any one of the first class of thirteen subembodiments;

[0071] 2. —X is NK, R is H, and Y, Z, X, R¹, R², R³, R⁴ and R⁵ are as defined in any one of the first class of thirteen subembodiments;

[0072] 3. —X—R is —N-Me₂, and Y, Z, X, R¹, R², R³, R⁴ and R⁵ are as defined in any one of the first class of thirteen subembodiments;

[0073] 4. —X—R is —NH-cPe (cyclic pentane), and Y, Z, X, R¹, R², R³, R⁴ and R⁵ are as defined in any one of the first class of thirteen subembodiments;

[0074] 5. —X—R is —N═O, and Y, Z, X, R, R¹, R², R³, R⁴ and R⁵ are as defined in any one of the first class of thirteen subembodiments;

[0075] 6. —X is S, and Y, Z, X, R, R¹, R², R³, R⁴ and R⁵ are as defined in any one of the first class of thirteen subembodiments;

[0076] 7. —X—R is —S-Me, and Y, Z, X, R¹, R², R³, R⁴ and R⁵ are as defined in any one of the first class of thirteen subembodiments;

[0077] 8. —X—R is —S-MeSMe, and Y, Z, X, R¹, R², R³, R⁴ and R⁵ are as defined in any one of the first class of thirteen subembodiments; and

[0078] 9. —X—R is —S-cPe, and Y, Z, X, R¹, R², R³, R⁴ and R⁵ are as defined in any one of the first class of thirteen subembodiments.

[0079] Preferred species of dihydro-alkyloxy-benzyl-oxopyrimidines are defined when:

[0080] 1. —X—R is —N-Me₂, Y is methyl, Z is methyl, R¹ and R⁵ are fluorine, and R², R³ and R⁴ are hydrogen (MC 1220);

[0081] 2. —X—R is —NH-cPe (cyclic pentane), Y is methyl, Z is methyl, R¹ and R⁵ are fluorine, and R², R³ and R⁴ are hydrogen (MC 1129);

[0082] 3. —X—R is —N═O, Y is methyl, Z is methyl, R¹ and R⁵ are fluorine, and R², R³ and R⁴ are hydrogen (MC 1237);

[0083] 4. —X—R is —S-Me, Y is methyl, Z is methyl, R¹ and R⁵ are fluorine, and R², R³, and R⁴ are hydrogen (MC 1060);

[0084] 5. —X—R is —S-MeSMe, Y is methyl, Z is methyl, R¹ and R⁵ are fluorine, and R², R³ and R⁴ are hydrogen (MC 1214); and

[0085] 6. —X—R is —S-cPe, Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen (MC 1047).

[0086] Other preferred species of dihydro-alkyloxy-benzyl-oxopyrimidines are those listed in table 1 and table 2. TABLE 1 Physical and Chemical Data of MC Compounds

(A) Compd. X Y Z R R¹ R² R³ R⁴ R⁵ m.p., ° C. Recryst. Solvent % yield Formula^(a) MC 507 O H H 2,5-Me₂-c-hex H H H H H 130-132 Petrol. Ether/diethyl ether 22 C₁₉H₂₄N₂O₂ MC 508 O H H 4,5-Me₂-c-hex H H H H H 132-134 Petrol. Ether/diethyl ether 28 C₁₉H₂₄N₂O₂ MC 512 O H H 3,5-Me₂-c-hex H H H H H 178-181 Petrol. Ether/diethyl ether 12 C₁₉H₂₄N₂O₂ MC 531 O Me H 2,5-Me₂-c-hex H H H H H 196-198 Petrol. Ether/diethyl ether 18 C₂₀H₂₆N₂O₂ MC 1114 O H H Sec-but F H H H F 87-88 Petrol. Ether/diethyl ether 28 C₁₅H₁₆F₂N₂O₂ MC 1103 O H H c-pent F H H H F 183.5-184.5 Benzene 52 C₁₆H₁₆F₂N₂O₂ MC 843 S H H beozyloxymeth H H H H H 181-183 Cyclohexane/benzene 38 C₁₉H₁₈N₂O₂S MC 796 S H Ph Sec-but H H H H H 157-158 n-hexane/cyclohexane 78 C₂₁H₂₂N₂OS MC 890 S H Me Iso-prop H H H H H 118-119 n-hexane 88 C₁₅H₁₈N₂OS MC 892 S H Me c-pent H H H H H 95-96 n-hexane 65 C₁₇H₂₀N₂OS MC 898 S H Me c-hex H H H H H 142-143 n-hexane 59 C₁₈H₂₂N₂OS MC 899 S H Et Iso-prop H H H H H 144-145 Cyclohexane 85 C₁₆H₂₀N₂OS MC 900 S H Et c-pent H H H H H 168-169 Cyclohexane 69 C₁₈H₂₂N₂OS MC 903 S H Et c-hex H H H H H 175.5-176.5 Cyclohexane 60 C₁₉H₂₄N₂OS MC 806 S H H Sec-but Me H H H H 118-119 n-hexane/cyclohexane 67 C₁₆H₂₀N₂OS MC 842 S H H c-pent Me H H H H 142-144 Cyclohexane 61 C₁₇H₂₀N₂OS MC 809 S H H Sec-but H H Me H H 107.5-108.5 n-hexane 56 C₁₆H₂₀N₂OS MC 817 S H H Sec-but NO₂ H H H H 148.0-148.5 Cyclohexane/benzene 68 C₁₅H₁₇N₃O₃S MC 897 S H H Sec-but H NO₂ H H H 127-128 Cyclohexane/benzene 54 C₁₅H₁₇N₃O₃S MC 863 S H H Sec-but H H NO₂ H H 128-130 Petrol. Ether/diethyl ether 100 C₁₅H₁₇N₃O₃S MC 854 S H H Sec-but Cl H H H H 120-121 n-hexane/cyclobexane 58 C₁₅H₁₇N₃O₃S MC 857 S H H Sec-but H Cl H H H 98-99 Cyclohexane 92 C₁₅H₁₇N₃O₃S MC 859 S H H Sec-but H H Cl H H 125-126 Cyclohexane 74 C₁₅H₁₇ClN₂OS MC 880 S H H Sec-but F H H H H 106-107 n-hexane/cyclohexane 68 C₁₅H₁₇ClN₂OS MC 884 S H H Sec-but H F H H H 96-97 Cyclohexane 67 C₁₅H₁₇FN₂OS MC 889 S H H Sec-but H H F H H 98-99 n-hexane 94 C₁₅H₁₇FN₂OS MC 825 S H H Sec-but NH₂ H H H H 143-144 Cyclohexane/benzene 74 C₁₅H₁₉N₂OS MC 960 S H H Sec-but H H NH₂ H H 128-130 Cyclohexane 77 C₁₃N₁₉N₃OS MC 868 S H H Sec-but CF₃ H H H H 125-126 Cyclohexane 89 C₁₆H₁₇F₃N₂OS MC 959 S H H Sec-but H H CF₃ H H 144-145 Cyclohexane 75 C₁₆H₁₇F₃N₂OS MC 952 S H H Sec-but OMe H H H H 123-124 Cyclohexane 69 C₁₆H₂₀N₂O₂S MC 957 S H H Sec-but H OMe H H H 78-80 n-hexane/Cyclohexane 71 C₁₆H₂₀N₂O₂S MC 964 S H H Sec-but H H OMe H H 112-113 Cyclohexane 63 C₁₆H₂₀N₂O₂S MC 1041 S H H Sec-but H F H H H 122-123 Cyclohexane 68 C₁₅H₁₆F₂N₂OS MC 1042 S H H Sec-but H Me H H H 119-120 n-hexane 72 C₁₇H₂₂N₂OS MC877 S H H Me Cl H H H Cl 237-238 benzene 98 C₁₂H₁₀Cl₂N₂OS MC878 S H H iso-prop Cl H H H Cl 230-231 benzene 81 C₁₄H₁₄Cl₂N₂OS MC886 S H H n-but Cl H H H Cl 153-154 cyclohexane 62 C₁₅N₁₆Cl₂N₂OS MC885 S H H iso-but Cl H H H Cl 143.5-144.5 cyclohexane 56 C₁₅H₁₆Cl₂N₂OS MC815 S H H sec-but Cl H H H Cl 183-184 cyclohexane/benzene 55 C₁₅N₁₆Cl₂N₂OS MC888 S H H c-pent Cl H H H Cl 185-186 cyclohexane 54 C₁₆H₁₆Cl₂N₂OS MC891 S H H c-hex Cl H H H Cl 200-201 cyclohexane/benzene 49 C₁₇H₁₈Cl₂N₂OS MC871 S H H Me F H H H F 197-198 benzene 95 C₁₂H₁₀F₂N₂OS MC860 S H H iso-prop F H H H F 174-175 cyclohexane 74 C₁₄H₁₄F₂N₂OS MC872 S H H n-but F H H H F 126-127 cyclohexane 46 C₁₅N₁₆F₂N₂OS MC866 S H H iso-but F H H H F 136-137 cyclohexane 49 C₁₅H₁₆F₂N₂OS MC848 S H H sec-but F H H H F 149-150 n-hexane/cyclohexane 48 C₁₅H₁₆F₂N₂OS MC867 S H H c-pent F H H H F 168-169 cyclohexane 45 C₁₆H₁₆FN₂OS MC870 S H H c-hex F H H H F 164-165 cyclohexane 40 C₁₇H₁₈F₂N₂OS MC1001 S H Me iso-prop Cl H H H Cl   196-196.5 cyclohexane/benzene 52 C₁₅H₁₆Cl₂N₂OS MC996 S H Me c-pent Cl H H H Cl 181-182 cyclohexane 45 C₁₇H₁₈Cl₂N₂OS MC1016 S H Me c-hex Cl H H H Cl 211-212 cyclohexane/benzene 42 C₁₈H20Cl₂N₂OS MC1000 S H Et iso-prop Cl H H H Cl 166-168 diethyl ether 54 C16H₁₈Cl₂N₂OS MC1002 S H Et c-pent Cl H H H Cl 168-169 diethyl ether 40 C₁₈H₂₀Cl₂N₂OS MC1003 S H Et c-hex Cl H H H Cl 198-199 cyclohexane 41 C₁₉H₂₂Cl₂N₂OS MC1007 S H Me iso-prop F H H H F 155-156 cyclohexane 53 C₁₅H₁₆F₂N₂OS MC1044 S H Me iso-but F H H H F 159-160 cyclohexane 49 C₁₆H₁₈F₂N₂OS MC1045 S H Me n-but F H H H F 149-150 cyclohexane 58 C₁₆H₁₈F₂N₂OS MC1110 S H Me sec-but F H H H F 133-134 n-hexane 75 C₁₆H₁₈F₂N₂OS MC1008 S H Me c-pent F H H H F 165.5-166.5 cyclohexane 60 C₁₇H₁₈F₂N₂OS MC1013 S H Me c-hex F H H H F 206-207 benzene 44 C₁₈H₂₀F₂N₂OS MC1005 S H Et iso-prop F H H H F 149-150 cyclohexane 40 C₁₆H₁₈F₂N₂OS MC1006 S H Et c-pent F H H H F 141-143 cyclohexane 45 C₁₈H₂₀F₂N₂OS MC1014 S H Et c-hex F H H H F 154-155 cyclohexane 51 C₁₉H₂₂F₂N₂OS MC971 S H Me iso-prop CH═CH—CH═CH H H H 161-162 n-hexane/cyclohexane 58 C₁₉H₂₀N₂OS MC972 S H Me c-pent CH═CH—CH═CH H H H 140-141 n-hexane/cyclohexane 49 C₂₁H₂₂N₂OS MC974 S H Me c-hex CH═CH—CH═CH H H H 177-178 n-hexane 45 C₂₂H₂₄N₂OS MC969 S H Et iso-prop CH═CH—CH═CH H H H 163-164 cyclohexane 54 C₂₀H₂₂N₂OS MC973 S H Et c-pent CH═CH—CH═CH H H H oil — 48 C₂₂H₂₄N₂OS MC975 S H Et c-hex CH═CH—CH═CH H H H 126-127 n-hexane 41 C₂₃H₂₆N₂OS MC844 S Me H sec-but Me H H H H 177-178 cyclohexane 55 C₁₇H₂₂N₂OS MC845 S Me H sec-but H H Me H H 127-128 n-hexane 61 C₁₇H₂₂N₂OS MC925 S Me H sec-but H NO₂ H H H 163-164 cyclohexane/benzene 88 C₁₆H₁₉N₃O₃S MC924 S Me H sec-but H H NO₂ H H 178-180 cyclohexane/benzene 100 C₁₆H₁₉N₃O₃S MC909 S Me H sec-but Cl H H H H 170-171 cyclohexane 68 C₁₆H₁₉ClN₂OS MC910 S Me H sec-but H Cl H H H 145-146 cyclohexane 75 C₁₆H₁₉ClN₂OS MC911 S Me H sec-but H H Cl H H 163-165 cyclohexane 79 C₁₆H₁₉ClN₂OS MC913 S Me H sec-but F H H H H 120.5-121.5 cyclohexane 65 C₁₆H₁₉FN₂OS MC918 S Me H sec-but H F F H H 146-147 cyclohexane 72 C₁₆H₁₉FN₂OS MC919 S Me H sec-but H H H H H 154-155 cyclohexane 69 C₁₆H₁₉FN₂OS MC912 S Me H Me Cl H H H Cl 206-261 benzene 93 C₁₃H₁₂Cl₂N₂OS MC914 S Me H iso-prop Cl H H H Cl 241-242 cyclohexane/benzene 78 C₁₅H₁₆Cl₂N₂OS MC920 S Me H n-but Cl H H H Cl 179-180 cyclohexane 52 C₁₆H₁₈Cl₂N₂OS MC916 S Me H iso-but Cl H H H Cl 208-209 cyclobexane 63 C₁₆H₁₈Cl₂N₂OS MC850 S Me H sec-but Cl H H H Cl 204-205 cyclohexane 53 C₁₆H₁₈Cl₂N₂OS MC915 S Me H c-pent Cl H H H Cl 252-253 cyclohexane/benzene 49 C₁₇H₁₈Cl₂N₂OS MC917 S Me H c-hex Cl H H H Cl 237-238 cyclohexane 48 C₁₈H₂₀Cl₂N₂OS MC869 S Me H Me F H H H F 218.5-219.5 benzene 92 C₁₃N₁₂F₂N₂OS MC881 S Me H iso-prop F H H H F 164-165 cyclohexanc 76 C₁₅H₁₆F₂N₂OS MC905 S Me H n-but F H H H F 178-179 cyclohexane 65 C₁₆H₁₈F₂N₂OS MC921 S Me H iso-but F H H H F 161-162 cyclohexane 59 C₁₆H₁₈F₂N₂OS MC849 S Me H sec-but F H H H F 128-129 n-hexane 49 C₁₆H₁₈F₂N₂OS MC922 S Me H c-pent F H H H F 192-193 cyclohexane 54 C₁₇H₁₈F₂N₂OS MC923 S Me H c-hex F H H H F 191-192 cyclohexane 49 C₁₈H₂₀F₂N₂OS MC1060 S Me Me Me F H H H F 202-203 cyclohexane/benzene 49 C₁₄H₁₄F₂N₂OS MC1109 S Me Me sec-but F H H H F 135-136 cyclohexane 55 C₁₇H₂₀F₂N₂OS MC1047 S Me Me c-pent F H H H F 196-197 cyclohexane 60 C₁₈H₂₀F₂N₂OS MC798 S Et H sec-but H H H H H 140-141 n-hexane 47 C₁₇H₂₂N₂OS MC1037 S Et H iso-prop F H H H F 174-175 benzene 78 C₁₆H₁₈F₂N₂OS MC1038 S Et H sec-but F H H H F 150-151 n-hexane/cyclohexane 62 C₁₇H₂₀F₂N₂OS MC804 S Et H sec-but CH═CH—CH═CH H H H 198.5-199.5 cyclohexane 42 C₂₁H₂₄N₂OS MC1039 S i-pro H iso-prop F H H H F 167-168 n-hexane 76 C₁₇H₂₀F₂N₂OS MC852 S allyl H sec-but H H H H H 127.5-128.5 cyclohexane 68 C₁₈H₂₂N₂OS MC856 S n-pro H sec-but H H H H H 108-109 n-hexane 42 C₁₈H₂₄N₂OS MC834 S n-but H sec-but H H H H H oil — 32 C₁₉H₂₆N₂OS MC1119 NH H H ethyl F H H H F 138-140 n-hexane/cyclohexane 50 C₁₃H₁₃F₂N₃O MC1078 NH H H n-prop F H H H F 136-137 cyclohexane 49 C₁₄H₁₅F₂N₃O MC979 NH H H iso-prop F H H H F 150-151 diethyl ether 58 C₁₄H₁₅F₂N₃O MC980 NH H H c-prop F H H H F 183-184 cyclohexane/benzene 68 C₁₄H₁₃F₂N₃O MC1077 NH H H n-but F H H H F 130-131 n-hexane 60 C₁₅H₁₇F₂N₃O MC945 NH H H sec-but F H H H F 140-141 diethyl ether 80 C₁₅H₁₇F₂N₃O MC1043 NH H H MeOethyl F H H H F 120-121 acetonitrile 78 C₁₄H₁₅F₂N₃O₂ MC1022 NH H H c-pent F H H H F oil — 74 C₁₆H₁₇F₂N₃O MC1049 NH H H c-hex F H H H F 143-144 diethyl ether 45 C₁₇H₁₉F₂N₃O MC1048 NH H Me c-pent F H H H F oil — 48 C₁₇H₁₉F₂N₃O MC1118 NH Me H iso-prop F H H H F 165-166 n-hexane 53 C₁₅H₁₇F₂N₃O MC1130 NH Me H sec-but F H H H F oil — 56 C₁₆H₁₉F₂N₃O MC1050 NH Me H c-pent F H H H F 115-117 n-hexane/cyclohexane 60 C₁₇H₁₉F₂N₃O MC1105 NH Me H benzyl F H H H F 182-183 cyclohexane/benzene 82 C₁₉H₁₇F₂N₃O MC1129 NH Me Me c-pent F H H H F oil — 38 C₁₈H₂₁F₂N₃O MC1167 NH H H Me F H H H F 202-203 acetonitrile 39 C₁₂H₁₁F₂N₃O MC1168 NH Me H Me F H H H F 210-211 acetonitrile 48 C₁₃H₁₃F₂N₃O MC1186 NH Me H n-prop F H H H F 156-157 acetonitrile 62 C₁₅H₁₇F₂N₃O MC1185 NH Me H n-but F H H H F 192-193 acetonitrile 68 C₁₆H₁₉F₂N₃O MC1178 NH H Me Me F H H H F 145-146 acetonitrile 34 C₁₃H₁₃F₂N₃O MC1190 NH H Me n-prop F H H H F oil — 45 C₁₅H₁₇F₂N₃O MC1191 NH H Me iso-prop F H H H F oil — 54 C₁₅H₁₇F₂N₃O MC1189 NH H Me n-but F H H H F oil — 55 C₁₆H₁₉F₂N₃O MC1192 NH H Me sec-but F H H H F oil — 59 C₁₆H₁₉F₂N₃O MC1180 NH H Me c-hex F H H H F oil — 62 C₁₈H₂₁F₂N₃O MC1170 NH Me Me Me F H H H F 193-194 cyclohexane/benzene 34 C₁₄H₁₅F₂N₃O MC1187 NH Me Me n-but F H H H F oil — 49 C₁₇H₂₁F₂N₃O MC1181 NH Me Me c-hex F H H H F oil — 54 C₁₉H₂₃F₂N₃O MC1182 N H H Me₂ F H H H F 210-211 cyclohexane/benzene 88 C₁₃H₁₃F₂N₃O MC1183 N H H Me-piperaz F H H H F 195-196 acetonitrile 84 C₁₆H₁₆F₂N₄O MC1188 N H H morph F H H H F 215-216 acetonitrile 75 C₁₅H₁₅F₃N₃O₂ MC1193 N H H thiomorph F H H H F 233-234 acetonitrile 78 C₁₅H₁₅F₂N₃OS MC1194 N H H piperid F H H H F 209-210 acetonitrile 68 C₁₆H₁₇F₂N₃O MC1196 N H H pyrrolid F H H H F 233-234 acetonitrile 52 C₁₃H₁₅F₂N₃O MC1202 N H H Et₂ F H H H F 159-160 acetonitrile 43 C₁₅H₁₇F₂N₃O MC1204 N H H (n-prop)₂ F H H H F 111-112 n-hexane 32 C₁₇H₂₁F₂N₃O MC1195 N Me H Me₂ F H H H F 237-238 acetonitrile 80 C₁₄H₁₅F₂N₃O MC1203 N Me H Me-piperaz F H H H F 235-236 acetonitrile 62 C₁₇H₂₀F₂N₄O MC1205 N Me H morph F H H H F 244-245 acetonitrile 65 C₁₆H₁₇F₂N₃O₂ MC1206 N Me H thiomorph F H H H F 255-256 acetonitrile 54 C₁₆H₁₇F₂N₃OS MC1137 S Me Me iso-prop F H H H F 177-178 n-hexane/cyclohexane 45 C₁₆H₁₈F₂N₂OS MC1175 S Me Me n-but F H H H F 122-123 n-hexane 51 C₁₇H₂₀F₂N₂OS MC1153 S Me Me iso-but F H H H F 152-153 cyclohexane 58 C₁₇H₂₀F₂N₂OS MC1174 S Me Me c-hex F H H H F 208-209 n-hexane/cyclohexane 48 C₁₉H₂₂F₂N₂OS MC1161 S H H MeSMe F H H H F 159-160 cyclohexane/benzene 72 C₁₃N₁₂F₂N₂OS₂ MC1162 S Me H MeSMe F H H H F 183-184 cyclohexane/benzene 70 C₁₄H₁₄F₂N₂OS₂ MC1157 S Et H MeSMe F H H H F 153-154 cyclohexane 69 C₁₅H₁₆F₂N₂OS₂ MC1145 S i-pro H MeSMe F H H H F 158.5-160   cyclohexane 62 C₁₆H₁₈F₂N₂OS₂ MC1140 S H H MeSMe H H H H H 117.5-118   n-hexane 64 C₁₃H₁₄N₂OS₂

[0087] TABLE 2 Cytotoxicity and anti-HIV-1 Activity of MC Compounds. {μM} Compd. X Y Z R R¹ R² R³ R⁴ R⁵ CC₅₀ EC₅₀ SI^(d) MC 507 O H H 2,5-Me₂-c-hex H H H H H 143 3.5 40 MC 508 O H H 4,5-Me₂-c-hex H H H H H 58 6.4 9 MC 512 O H H 3,5-Me₂-c-hex H H H H H >200 30 >6.7 MC 531 O Me H 2,5-Me₂-c-hex H H H H H 138 3.5 39 MC 1114 O H H sec-but F H H H F 130 25 52 MC 1103 O H H c-pent F H H H F >200 20 >10 MC 843 S H H Benzoyloxy-methyl H H H H H >200 45 >4 MC 796 S H Ph sec-but H H H H H 61 >61 — MC 890 S H Me iso-prop H H H H H >200 .9 >222 MC 892 S H Me c-pent H H H H H 159 .6 333 MC 898 S H Me c-hex H H H H H 149 .6 248 MC 899 S H Et iso-prop H H H H H 200 .8 250 MC 900 S H Et c-pent H H H H H >200 1.0 >200 MC 903 S H Et c-hex H H H H H >200 1.3 >154 MC 806 S H H sec-but Me H H H H >200 1.8 >111 MC 842 S H H c-pent Me H H H H >200 3.4 >59 MC 809 S H H sec-but H H Me H H 200 0.6 333.3 MC 817 S H H sec-but NO₂ H H H H >200 0.25 >800 MC 897 S H H sec-but H NO₂ H H H 157 0.40 392 MC 863 S H H sec-but H H NO₂ H H 151 1.5 101 MC 854 S H H sec-but Cl H H H H 200 1 200 MC 857 S H H sec-but H Cl H H H 116 2 58 MC 859 S H H sec-but H H Cl H H 120 5 24 MC 880 S H H sec-but F H H H H 200 0.26 769 MC 884 S H H sec-but H F H H H >200 0.7 >286 MC 889 S H H sec-but H H F H H >200 8.7 23 MC 825 S H H sec-but NH₂ H H H H >200 21.2 >9 MC 960 S H H sec-but H H NH₂ H H >200 23 >8 MC 868 S H H sec-but CF₃ H H H H >200 32 6.2 MC 959 S H H sec-but H H CF₃ H H 200 25 8 MC 952 S H H sec-but OMe H H H H >200 1.96 >208 MC 957 S H H sec-but H OMe H H H >200 1.2 >166 MC 964 S H H sec-but H H OMe H H 147 14 10.5 MC 1041 S H H sec-but H F H F H >200 1.4 >143 MC 1042 S H H sec-but H Me H Me H 133 0.6 222 MC 877 S H H Me Cl H H H Cl >200 3.2 >62 MC 878 S H H iso-prop Cl H H H Cl >200 1.9 >105 MC 866 S H H n-but Cl H H H Cl >200 0.44 >454 MC 885 S H H iso-but Cl H H H Cl >200 0.45 >444 MC 815 S H H sec-but Cl H H H Cl >200 0.14 >1,428 MC 888 S H H c-pent Cl H H H Cl >200 0.4 >500 MC 891 S H H c-hex Cl H H H Cl >200 0.6 >333 MC 871 S H H Me F H H H F 200 0.81 247 MC 860 S H H iso-prop F H H H F >200 0.2 >1,000 MC 872 S H H n-but F H H H F 162 0.18 900 MC 866 S H H iso-but F H H H F 182 0.14 1,300 MC 848 S H H sec-but F H H H F 200 0.04 5,000 MC 867 S H H c-pent F H H H F >200 0.08 >2,500 MC 870 S H H c-hex F H H H F 200 0.08 2,500 MC 1001 S H Me iso-prop Cl H H H Cl 117 1.2 97.5 MC 996 S H Me c-pent Cl H H H Cl 78.3 1.0 78.3 MC 1016 S H Me c-hex Cl H H H Cl >200 2.9 >69 MC 1000 S H Et iso-prop Cl H H H Cl >200 0.4 >500 MC 1002 S H Et c-pent Cl H H H Cl 23.4 1.0 23.4 MC 1003 S H Et c-hex Cl H H H Cl >200 3.6 >55.5 MC 1007 S H Me iso-prop F H H H F 167 0.05 3,340 MC 1044 S H Me iso-but F H H H F >200 0.05 >4,000 MC 1045 S H Me n-but F H H H F >200 0.07 2,857 MC 1110 S H Me sec-but F H H H F >200 0.03 >6,666 MC 1008 S H Me c-pent F H H H F >200 0.03 >6,666 MC 1013 S H Me c-hex F H H H F >200 0.16 >1,250 MC 1005 S H Et iso-prop F H H H F 70 0.08 875 MC 1006 S H Et c-pent F H H H F 200 0.15 1,333 MC 1014 S H Et c-hex F H H H F 130 0.05 2,600 MC 971 S H Me iso-prop CH═CH—CH═CH H H H 119 1.1 108 MC 972 S H Me c-pent CH═CH—CH═CH H H H 93 0.5 186 MC 974 S H Me c-hex CH═CH—CH═CH H H H 45 0.14 321.4 MC 969 S H Et iso-prop CH═CH—CH═CH H H H 50 1.5 33.3 MC 973 S H Et c-pent CH═CH—CH═CH H H H 51 3.0 17 MC 975 S H Et c-hex CH═CH—CH═CH H H H 16.9 0.18 94 MC 844 S Me H sec-but Me H H H H >200 1.7 >118 MC 845 S Me H sec-but H H Me H H 26 0.8 32 MC 925 S Me H sec-but H NO₂ H H H >200 0.35 >571 MC 924 S Me H sec-but H H NO₂ H H >200 2 >100 MC 909 S Me H sec-but Cl H H H H >200 0.27 >741 MC 910 S Me H sec-but H Cl H H H >200 0.96 >208 MC 911 S Me H sec-but H H Cl H H >200 9.5 20 MC 913 S Me H sec-but F H H H H 140 0.41 341 MC 918 S Me H sec-but H F H H H >200 1.2 >166 MC 919 S Me H sec-but H H F H H 105 11 9.5 MC 912 S Me H Me Cl H H H Cl >200 3.2 >62 MC 914 S Me H iso-prop Cl H H H Cl >200 1.3 >154 MC 920 S Me H n-but Cl H H H Cl   >200^(e) 1.17 >171 MC 916 S Me H iso-but Cl H H H Cl >200 1.2 >166 MC 850 S Me H sec-but Cl H H H Cl >200 0.05 >4,000 MC 915 S Me H c-pent Cl H H H Cl >200 1.8 >111 MC 917 S Me H c-hex Cl H H H Cl >200 22 >9 MC 869 S Me H Me F H H H F 200 0.19 1,053 MC 881 S Me H iso-prop F H H H F >200 0.05 >4,000 MC 905 S Me H n-but F H H H F >200 0.08 >2,500 MC 921 S Me H iso-but F H H H F 64 0.1 640 MC 849 S Me H sec-but F H H H F 80 0.001 8,000 MC 922 S Me H c-pent F H H H F >200 0.08 >2,500 MC 923 S Me H c-hex F H H H F >200 0.09 >2,222 MC 1060 S Me Me Me F H H H F >200 0.04 >5,000 MC 1109 S Me Me sec-but F H H H F 200 0.03 6,666 MC 1047 S Me Me c-pent F H H H F >200 0.009 >22,222 MC 798 S Et H sec-but H H H H H >200 1.0 >200 MC 1037 S Et H iso-prop F H H H F 65 0.2 326 MC 1038 S Et H sec-but F H H H F >200 0.1 >2,000 MC 804 S Et H sec-but CH═CH—CH═CH H H H >200 5.3 >34 MC 1039 S iso-propyl H iso-prop F H H H F >200 0.4 >500 MC 852 S allyl H sec-but H H H H H >200 3 >67 MC 856 S n-prop H sec-but H H H H H 190 12 16 MC 834 S n-but H sec-but H H H H H >200 >200 — MC 1119 NH H H ethyl F H H H F >200 0.8 >250 MC 1078 NH H H n-prop F H H H F 200 0.11 1,818 MC 979 NH H H iso-prop F H H H F >200 0.38 >526 MC 980 NH H H c-prop F H H H F >200 3.17 >63 MC 1077 NH H H n-but F H H H F 100 0.10 1,000 MC 945 NH H H sec-but F H H H F >200 0.13 >1,540 MC 1043 NH H H MeOethyl F H H H F >200 0.8 >250 MC 1022 NH H H c-pent F H H H F >200 0.09 >2,222 MC 1049 NH H H c-hex F H H H F 66 0.14 471 MC 1048 NH H Me c-pent F H H H F 75 0.03 2,500 MC 1118 NH Me H iso-prop F H H H F 190 0.03 6,333 MC 1130 NH Me H sec-but F H H H F 200 0.07 2,857 MC 1050 NH Me H c-pent F H H H F >200 0.02 >10,000 MC 1105 NH Me H benzyl F H H H F 50 0.50 100 MC 1129 NH Me H c-pent F H H H F 90 0.02 4,500 MC 1167 NH H H Me F H H H F >200 1.5 >133 MC 1168 NH Me H Me F H H H F 135 0.4 335 MC 1186 NH Me H n-prop F H H H F >200 0.02 >10,000 MC 1185 NH Me H n-but F H H H F >200 0.02 >10,000 MC 1178 NH H Me Me F H H H F 106 0.11 964 MC 1190 NH H Me n-prop F H H H F 103 0.02 5,150 MC 1191 NH H Me iso-prop F H H H F 115 0.03 3,830 MC 1189 NH H Me n-but F H H H F 52 0.03 1,730 MC 1192 NH H Me sec-but F H H H F 86 0.04 2,150 MC 1180 NH H Me c-hex F H H H F 56 0.02 2,545 MC 1170 NH Me Me Me F H H H F 200 0.03 >6,666 MC 1187 NH Me Me n-but F H H H F 83 0.01 8,300 MC 1181 NH Me Me c-hex F H H H F 58 0.03 2,231 MC 1182 N H H Me₂ F H H H F >200 0.05 >4,000 MC 1183 N H H Me-piperaz F H H H F >200 7.1 >28 MC 1188 N H H morph F H H H F >200 0.6 >333 MC 1193 N H H thiomorph F H H H F >200 0.05 >4,000 MC 1194 N H H piperid F H H H F >200 0.02 >10,000 MC 1196 N H H pyrrolid F H H H F >200 2.1 >95 MC 1202 N H H Et₂ F H H H F >200 0.26 >769 MC 1204 N H H (n-prop)₂ F H H H F >200 3.8 >53 MC 1195 N Me H Me₂ F H H H F >200 0.02 >10,000 MC 1203 N Me H Me-piperaz F H H H F >200 0.36 >555 MC 1205 N Me H morph F H H H F >200 0.047 >4,255 MC 1206 N Me H thiomorph F H H H F >200 0.09 >2,222 MC 1137 S Me Me iso-prop F H H H F 200 0.007 28,571 MC 1175 S Me Me n-but F H H H F 112 0.008 14,000 MC 1153 S Me Me iso-but F H H H F >200 0.01 >20,000 MC 1174 S Me Me c-hex F H H H F >200 0.018 >11,111 MC 1047+ S Me Me c-pent F H H H F >200 0.002 >100,000 MC 1047− S Me Me c-pent F H H H F >200 0.7 >286 MC 1161 S H H MeSMe F H H H F >200 0.80 >250 MC 1162 S Me H MeSMe F H H H F 30 0.12 250 MC 1157 S Et H MeSMe F H H H F 50 0.11 454 MC 1145 S iso-propyl H MeSMe F H H H F 200 0.10 2,000 MC 1140 S H H MeSMe H H H H H >200 20 >10

[0088] In another embodiment the invention provides compounds defined by the foregoing species, embodiments, and subembodiments.

[0089] Stereoisomerism and Polymorphism

[0090] The compounds of the present invention may have asymmetric centers and occur as racemates, racemic mixtures, individual diastereomers or enantiomers, with all isomeric forms being included in the present invention. Compounds of the present invention having a chiral center may exist in and be isolated in optically active and racemic forms. Some compounds may exhibit polymorphism. The present invention encompasses racemic, optically-active, polymorphic, or stereoisomeric form, or mixtures thereof, of a compound of the invention, which possess the useful properties described herein. The optically active forms can be prepared by, for example, resolution of the racemic form by recrystallization techniques, by synthesis from optically-active starting materials, by chiral synthesis, or by chromatographic separation using a chiral stationary phase or by enzymatic resolution.

[0091] Opitically active forms of the compounds can be prepared using any method known in the art, including by resolution of the racemic form by recrystallization techniques, by synthesis from optically-active starting materials, by chiral synthesis, or by chromatographic separation using a chiral stationary phase.

[0092] Examples of methods to obtain optically active materials include at least the following.

[0093] i) physical separation of crystals—a technique whereby macroscopic crystals of the individual enantiomers are manually separated. This technique can be used if crystals of the separate enantiomers exist, i.e., the material is a conglomerate, and the crystals are visually distinct;

[0094] ii) simultaneous crystallization—a technique whereby the individual enantiomers are separately crystallized from a solution of the racemate, possible only if the latter is a conglomerate in the solid state;

[0095] iii) enzymatic resolutions—a technique whereby partial or complete separation of a racemate by virtue of differing rates of reaction for the enantiomers with an enzyme;

[0096] iv) enzymatic asymmetric synthesis—a synthetic technique whereby at least one step of the synthesis uses an enzymatic reaction to obtain an enantiomerically pure or enriched synthetic precursor of the desired enantiomer;

[0097] v) chemical asymmetric synthesis—a synthetic technique whereby the desired enantiomer is synthesized from an achiral precursor under conditions that produce asymmetry (i.e., chirality) in the product, which may be achieved using chiral catalysts or chiral auxiliaries;

[0098] vi) diastereomer separations—a technique whereby a racemic compound is reacted with an enantiomerically pure reagent (the chiral auxiliary) that converts the individual enantiomers to diastereomers. The resulting diastereomers are then separated by chromatography or crystallization by virtue of their now more distinct structural differences and the chiral auxiliary later removed to obtain the desired enantiomer;

[0099] vii) first- and second-order asymmetric transformations—a technique whereby diastereomers from the racemate equilibrate to yield a preponderance in solution of the diastereomer from the desired enantiomer or where preferential crystallization of the diastereomer from the desired enantiomer perturbs the equilibrium such that eventually in principle all the material is converted to the crystalline diastereomer from the desired enantiomer. The desired enantiomer is then released from the diastereomer;

[0100] viii) kinetic resolutions—this technique refers to the achievement of partial or complete resolution of a racemate (or of a further resolution of a partially resolved compound) by virtue of unequal reaction rates of the enantiomers with a chiral, non-racemic reagent or catalyst under kinetic conditions;

[0101] ix) enantiospecific synthesis from non-racemic precursors—a synthetic technique whereby the desired enantiomer is obtained from non-chiral starting materials and where the stereochemical integrity is not or is only minimally compromised over the course of the synthesis;

[0102] x) chiral liquid chromatography—a technique whereby the enantiomers of a racemate are separated in a liquid mobile phase by virtue of their differing interactions with a stationary phase (including via chiral HPLC). The stationary phase can be made of chiral material or the mobile phase can contain an additional chiral material to provoke the differing interactions;

[0103] xi) chiral gas chromatography—a technique whereby the racemate is volatilized and enantiomers are separated by virtue of their differing interactions in the gaseous mobile phase with a column containing a fixed non-racemic chiral adsorbent phase;

[0104] xii) extraction with chiral solvents—a technique whereby the enantiomers are separated by virtue of preferential dissolution of one enantiomer into a particular chiral solvent;

[0105] xiii) transport across chiral membranes—a technique whereby a racemate is placed in contact with a thin membrane barrier. The barrier typically separates two miscible fluids, one containing the racemate, and a driving force such as concentration or pressure differential causes preferential transport across the membrane barrier. Separation occurs as a result of the non-racemic chiral nature of the membrane that allows only one enantiomer of the racemate to pass through.

[0106] Chiral chromatography, including simulated moving bed chromatography, is used in one embodiment. A wide variety of chiral stationary phases are commercially available.

[0107] Definitions

[0108] When any variable occurs more than one time in any constituent or in formula A of this invention, its definition on each occurrence is independent of its definition at every other occurrence. Also, combinations of substituents and/or variables are permissible only if such combinations result in stable compounds.

[0109] As used herein except where noted, “alkyl” is intended to include both branched- and straight-chain saturated aliphatic hydrocarbon groups having the specified number of carbon atoms; “Halogen” or “Hal” as used herein, means fluoro, chloro, bromo and iodo.

[0110] As used herein, with exceptions as noted, “aryl” is intended to mean any stable monocyclic, bicyclic or tricyclic carbon ring of up to 7 members in each ring, wherein at least one ring is aromatic as defined by the Huckel 4n+2 rule. Examples of aryl ring systems include phenyl, naphthyl, tetrahydronaphthyl, biphenyl.

[0111] The term heterocycle or heterocyclic, as used herein except where noted represents a stable 5- to 7-membered monocyclic or stable 8- to 11-membered bicyclic heterocyclic ring which is either saturated or unsaturated, and which consists of carbon atoms and from one to three heteroatoms selected from the group consisting of N, O and S; and wherein the nitrogen and sulfur heteroatoms may optionally be oxidized, and the nitrogen heteroatom may optionally be quaternized, and including any bicyclic group in which any of the above-defined heterocyclic rings is fused to a benzene ring. The heterocyclic ring may be attached at any heteroatom or carbon atom which results in the creation of a stable structure.

[0112] The pharmaceutically-acceptable salts of the compounds of this invention that are capable of salt formation (in the form of water- or oil-soluble or dispersible products) include the conventional non-toxic salts or the quaternary ammonium salts of these compounds, which are formed, e.g., from inorganic or organic acids or bases.

[0113] Secondary Antiviral Constituents

[0114] The compositions of this invention may optionally contain a second anti-HIV agent. Exemplary agents include AZT, D4T, FTC (2′,3′-dideoxy-3′-thia-5-fluorocytidine); 3TC (Epivir, Glaxo Wellcome, Inc.), AZDU (3′-Azido-2′,3′-dideoxyuridine); 141W94 (amprenavir, Glaxo Wellcome, Inc.); Viramune (nevirapine), Rescriptor (delavirdine); or DMP-266 (efavirenz). Other examples of anti-HIV agents include DDI, DDC, Delaviridine, β-LddA, β-L-3′-azido-d5FC, carbovir, acyclovir, interferon, stavudine, CS-92 (3′-azido-2′,3′-dideoxy-5-methyl-cytidine), 3′-azido nucleosides, and β-D-dioxolane nucleosides such as β-D-dioxolanylguanine (DXG), β-D-dioxolanyl-2,6-diaminopurine (DAPD), and β-D-dioxolanyl-6-chloropurine (ACP).

[0115] Preferred protease inhibitors include indinavir ({1(1,S,2R),5(S)}-2,3,5-trideoxy-N-(2,3-dihydro-2-hydroxy-1H-inden-1-yl)-5-{2-{{(1,1-dimethylethyl)amino}carbonyl}-4-(3-pyridinylmethyl)-1-piperazinyl}-2-(phenylmethyl)-D-erythro-pentoamide sulfate; Merck), nelfinavir (Agouron), ritonavir (Abbot), and saquinavir (Invirase; Roche).

[0116] Nonlimiting examples of other compounds that can be administered in combination or alternation with the compounds of the present invention to augment the properties of the drug on administration include abacavir: (1S,4R)-4-{2-amino-6-cyclopropyl-amino)-9H-purin-9-yl}-2-cyclopentene-1-methanol succinate (1592U89, a carbovir analog; Glaxo Wellcome); zidovudine: AZT, 3′-azido-3′-deoxythymidine (Glaxo Wellcome); BILA 1906: N-{1S-{{{3-{2S-{(1,1-dimethylethyl)amino}carbonyl}-4R-}3-pyridinylmethyl)-thio}-1-piperidinyl}-2R-hydroxy-1S-(phenylmethyl)propyl}amino}carbonyl}-2-methylpropyl}-2-quinolinecarboxamide (Bio Mega/Boehringer-Ingelheim); BILA 2185: N-(1,1-dimethylethyl)-1-{2S-{{2-2,6-dimethylphenoxy)-1-oxoethyl}amino}-2R-hydroxy-4-phenylbutyl}4R-pyridinylthio)-2-piperidinecarboxamide (Bio Mega/Boehringer-Ingelheim); BM+51.0836:triazoloisoindolinone derivative; BMS 186,318: aminodiol derivative HIV-1 protease inhibitor (Bristol-Myers-Squibb); d4API: 9-{2,5-dihydro-5-(phosphonomethoxy)-2-furanel}adenine (Gilead); stavudine: d4T, 2′,3′-didehydro-3′-deoxythymidine (Bristol-Myers-Squibb); efavirenz: DMP-266, a 1,4-dihydro-2H-3,1-benzoxazin-2-one; HBY097: S-4-isopropoxycarbonyl-6-methoxy-3-(methylthiomethyl)-3,4-dihydroquinoxalin-2(1H)-thione; HEPT: 1-{(2-hydroxyethoxy)methyl}6-(phenylthio)-thymine; KNI-272: (2S,3S)-3-amino-2-hydroxy-4-phenylbutyric acid-containing tripeptide; L-697,593; 5-ethyl-6-methyl-3-(2-phthalimido-ethyl)pyridin-2(1H)-one; L-735,524: hydroxy-aminopentane amide HIV-1 protease inhibitor (Merck); L-697,661: 3-{{(-4,7-dichloro-1,3-benzoxazol-2-yl)methyl}amino}-5-ethyl-6-methylpyridin-2(1H)-one; L-FDDC: (−)-β-L-5-fluoro-2′,3′-dideoxycytidine; L-FDOC: (−)-β-L-5-fluoro-dioxolane cytosine; 6-benzyl-1-ethoxymethyl-5-isopropyluracil (I-EBU; Triangle/Mitsubishi); nevirapine: 11-cyclopropyl-5,11-dihydro-4-methyl-6H-dipyridol{3,2-b:2′,3′-e}diazepin-6-one (Boehringer-Ingelheim); PFA: phosphonoformate (foscarnet; Astra); PMEA: 9-(2-phosphonylmethoxyethyl) adenine (Gilead); PMPA: (R)-9-(2-phosphonyl-methoxypropyl)adenine (Gilead); Ro 31-8959: hydroxythethylamine derivative HIV-1 protease inhibitor (Roche); RPI-3121: peptidyl protease inhibitor, 1-{(3 s)-3-(n-alpha-benzyloxycarbonyl)-1-asparginyl)-amino-2-hydroxy-4-phenylbutyryl}-n-tert-butyl-1-proline amide; 2720: 6-chloro-3,3-dimethyl-4-(isopropenyloxycarbonyl)-3,4-dihydro-quinoxalin-2(1H)thione; SC-52151: hydroxyethylurea isostere protease inhibitor (Searle); SC-55389A: hydroxyethyl-urea isostere protease inhibitor (Searle); TIBO R82150: (+)-(5S)-4,5,6,7-tetrahydro-5-methyl-6-(3-methyl-2-butenyl)imidazo {4,5,1-jk}{1,4}-benzodiazepin-2(1H)-thione (Janssen); TIBO 82913: (+)-(5S)-4,5,6,7,-tetrahydro-9-chloro-5-methyl-6-(3-methyl-2-butenyl)imidazo {4,5,1jk}-{1,4}benzodiazepin-2(1H)-thione (Janssen); TSAO-m3T: {2′,5′-bis-O-(tert-butyldimethylsilyl)-3′-spiro-5′-(4′-amino-1′,2′-oxathiole-2′,2′-dioxide)}-β-D-pentofiuranosyl-N-3-methylthymine; U90152: 1-{3-{(1-methylethyl)-amino}2-pyridinyl}-4-{{5-{(methylsulphonyl)-amino}-1H-indol-2yl}carbonyl}piperazine; UC: thiocarboxanilide derivatives (Uniroyal); UC-781 =N-{4-chloro-3-(3-methyl-2-butenyloxy)phenyl}-2-methyl-3-furancarbothioamide; UC-82=N-{4-chloro-3-(3-methyl-2-butenyloxy)phenyl}-2-methyl-3-thiophenecarbothioamide; VB 11,328: hydroxyethylsulphonamide protease inhibitor (Vertex); VX-478: amprenavir, 141W94, hydroxyethylsulphonamide protease inhibitor (Vertex/Glaxo Wellcome); XM 323: cyclic urea protease inhibitor (Dupont Merck), delaviridine (Pharmacia Upjohn), famciclovir, gancyclovir, and penciclovir.

[0117] In one embodiment,a compound of the present invention is administered in combination with LG1350, which has the following structure.

[0118] Synthetic Methods

[0119] Preparation of compounds of formula (I) can be achieved by the general procedures listed below.

[0120] Anhydrous pyridine (400 mmoles, 32.5 ml) was added with stirring under nitrogen atmosphere into an ice-cooled solution of 2,2-dimethyl-1,3-dioxane-4,6-dione (Meldrurm's acid) (165 mmoles, 23.75 g) in anhydrous dichloromethane (50 ml). The resulting solution was treated, over a 2 h period at 0° C. under nitrogen atmosphere, with a solution of crude arylacetyl chloride in anhydrous dichloromethane (50 ml). Arylacetyl chloride was prepared before use by refluxing the proper arylacetic acid (43.2 mmoles) with thionyl chloride (21.3 ml) under nitrogen atmosphere for 2 h. Then, the mixture was stirred for 2 h at room temperature, poured into crushed ice and treated with 2N HCl (100 ml). The organic layer was separated and the aqueous solution was extracted twice with dichloromethane (25 ml). The organic phase and the extracts were combined, washed with brine, dried and evaporated. The solid residue was dissolved in anhydrous methanol (250 ml) and the solution was refluxed for 20 h. After cooling, metal sodium (0.16 g-atoms, 3.68 g) was carefully added and the mixture was stirred until dissolution was complete. Alkyl halide (160 mmoles) was dropped into the solution and the resulting mixture was heated at reflux for 4-12 h. After cooling, the solvent was removed and the residue treated with water (200 ml) and extracted with chloroform (3×100 ml). The organic layer was washed with brine (2×100 ml), dried and evaporated to give the desired compound (3), which was purified by passing through a silica gel column (chloroform as eluent).

[0121] In the above reaction, arylacetic acid (Scheme “A”) or arylacetyl chloride can be replaced with the corresponding 1-arylacetylimidazolide (Scheme “B”) or with arylacetylethoxycarbonylanhydride, whereas the Meldrum's acid can be replaced with ethyl acetylacetate, ethyl alkylmalonate or ethyl alkylmalonate potassium salt, to give the proper ethyl arylacetylalkylacetates in high yields.

[0122] Preparation Of Compounds (I) (in Scheme B)With X=O (See Scheme A).

[0123] The proper methyl arylacetylalkylacetate (2) (10 mmoles) in methanol (50 ml) was added to a well-stirred suspension of O-methylisourea hydrogen sulphate (15 mmoles, 2.58 g) and calcium hydroxide (16 mmoles, 1.18 g) in water (50 ml). The resulting mixture was stirred at room temperature for 72 h, then concentrated, made acid (pH 5) with 0.5N acetic acid and extracted with ethyl acetate (3×50 ml). The combined organic extracts were washed with brine (100 ml), dried and evaporated to dryness. The residue was purified by crystallization from the proper solvent yielding pure 5-alkyl-6-benzyl-3,4-dihydro-2-methoxypyrimidin-4-one (4). This compound was then refluxed with the proper potassium alkoxide (100 mmoles of potassium metal in 20-30 ml of alcohol freshly distilled on sodium metal) under nitrogen atmosphere until starting material disappeared at the TLC control. After cooling, the mixture was concentrated, made acid (pH 5) with 0.5N acetic acid and extracted with ethyl acetate (3×50 ml). The combined extracts were washed once with brine (100 ml), dried and evaporated to give the required 2-alkoxy-5-alkyl-6-benzyl-3,4-dihydropyrimidin-4-one derivative (A), which was recrystallized from a suitable solvent or purified by column chromatography (silica gel; ethyl acetate:chloroform 1:1). Physical and chemical data of representative compounds of the invention are reported in table 1; cytotoxicity and anti-HIV-1 activity data are reported in table 2.

[0124] The proper ethyl arylacetylalkylacetate (31.5 mmoles) was successively added to a stirred solution of sodium metal (0.063 g-atoms) in 50 mL of absolute ethanol (50 ml) and thiourea (43 mmoles). The mixture was heated while stirring at reflux for 5 h. After cooling, the solvent was distilled in vacuo at 40-50° C. until dryness and the residue was dissolved in water (200 mL) and made acid (pH 5) with 0.5N acetic acid. The resulting precipitate (the crude 2-thiouracil derivative) was filtered under reduced pressure, washed with diethyl ether, vacuum dried at 80° C. for 12 h and then crystallized from the proper solvent (I).

[0125] Then, according to method A, iodomethane (8 mmoles, 1.13 g) was added to a suspension containing the proper 2-thiouracil derivative (4 mmoles) in anhydrous N,N-dimethylformamide (2 ml), and the resulting mixture was stirred at room temperature until the starting material disappeared at the TLC control (silica gel; n-hexane:ethyl acetate: methanol 12:3:1). Then the reaction content was poured on cold water (100 mL) and extracted with ethyl acetate (3×50 ml). The organic layers were collected, washed with a sodium thiosulfate solution (100 ml), brine (3×50 ml), dried and evaporated to furnish the crude 5-alkyl-6-benzyl-3,4-dihydro-2-methylthiopyrimidin-4-one (5) as a solid purified by crystallization.

[0126] Alternatively, according to methods B and C, potassium carbonate (4.2 mmoles) and the proper alkyl halide (4.4 mmoles) were added to a suspension containing 2-thiouracil derivative (4 mmoles) in anhydrous N,N-dimethylformamide (2 ml). The resulting mixture was stirred at room temperature (method B) or at 80° C. (method C) until starting material disappeared at the TLC control (silica gel; n-hexane:ethyl acetate:methanol 12:3:1). Then the reaction content was poured on cold water (200 mL), made acid (pH 5) with 0.5N acetic acid and extracted with ethyl acetate (3×50 ml). The organic layers were collected, washed with a sodium thiosulfate solution (100 ml), brine (100 ml), dried and evaporated to furnish 5-alkyl-6-benzyl-3,4-dihydro-2-methylthiopyrimidin-4-ones (6) and (7) as crude material which was then purified by column chromatography on silica gel (eluent: n-hexane:ethyl acetate:methanol 12:3:1) followed by crystallization. Physical and chemical data of representative compounds of the invention are reported in table 1. Cytotoxicity and anti-HIV-1 activity in vitro are reported in table 2.

[0127] Title derivatives were prepared according to the procedure described for the synthesis of compounds with X═S (I), using ethyl arylacetylalkylacetates and guanidine {2-amino-6-benzylpyrimidin-4-ones (8)} as starting materials. 2-Alkylaminoderivatives (9) were synthesized by heating the previously reported 5-alkyl-6-benzyl-3,4-dihydro-2-methylthio pyrimidin-4-ones with 20-30 ml of proper amine in a sealed tube at 170° C. for 24 h. Physical and chemical data of some compounds (9) are reported in table 1. Cytotoxicity and anti-HIV-1 activity in vitro are reported in table 2.

[0128] Assay Procedures for Results Reported in Tables 1 and 2

[0129] Compounds. Compounds were solubilized in DMSO at 200 mM and then diluted into culture medium.

[0130] Cells and viruses. MT-4, C8166, H9/IIIB and CEM cells were grown at 37° C. in a 5% CO₂ atmosphere in RPMI 1640 medium, supplemented with 10% fetal calf serum (FCS), 100 IU/mL penicillin and 100 μg/mL streptomycin. Cell cultures were checked periodically for the absence of mycoplasma contamination with a MycoTect Kit (Gibco). Human immunodeficiency virus type-1 (HIV-1, III_(B) strain) was obtained from supernatants of persistently infected H9/III_(B) cells. HIV-1 stock solution had a titres of 4.5×10⁶ 50% cell culture infectious dose (CCID₅₀)/ml.

[0131] HIV titration. Titration of HIV was performed in C8166 cells by the standard limiting dilution method (dilution 1:2, four replica wells per dilution) in 96-well plates. The infectious virus titre was determined by light microscope scoring of cytopathicity after 4 days of incubation and the virus titres were expressed as CCID₅₀/mL.

[0132] Anti-HIV assays. Activity of the compounds against HIV-1 and HIV-2 multiplication in acutely infected cells was based on the inhibition of virus-induced cytopathicity in MT-4 and C8166 cells, respectively. Briefly, 50 μL of culture medium containing 1×10⁴ cells were added to each well of flat-bottom microtiter trays containing 50 μl of culture medium with or without various concentrations of the test compounds. Then 20 μL of an HIV suspension containing 100 CCID₅₀ were added. After a 4-day incubation at 37° C., the number of viable cells was determined by the 3-(4,5-dimethylthiazol-1-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Cytotoxicity of the compounds was evaluated in parallel with their antiviral activity. It was based on the viability of mock-infected cells, as monitored by the MTT method.

[0133] RT assays. Assays were performed as follows. Briefly, purified rRT was assayed for its RNA-dependent polymerase-associated activity in a 50 μL volume containing: 50 mM Tris HCl (pH 7.8), 80 mM KCIl, 6 mM MgCl₂, 1 mM DTT, 0.1 mg/mL BSA, 0.3 OD₂₆₀ unit/mL template:primer {poly(rC)-oligo(dG)12-18} and 10 μM {³H}dGTP (1 Ci/mmol). After incubation for 30 min at 37° C., the samples were spotted on glass fiber filters (Whatman GF/A), and the acid-insoluble radioactivity was determined.

EXAMPLES Example 1 2-Cyclopentylthio-6-(2,6-difluorophenylmethyl)-3,4-dihydrogyrimidin-4-(3H)-one (MC867)

[0134] A mixture of 6-(2,6-difluorophenylmethyl)-1,2,3,4-tetrahydro-2-thiopyrimidin-4(3H)-one (0.16 g, 0.65 mmol; prepared as reported in scheme B), cyclopentyl bromide (0.11 g, 0.08 mL., 0.71 mmol) and potassium carbonate (0.09 g, 0.65 mmol) in 1 mL of anhydrous DMF was stirred at room temperature for 24 h. After treatment with cold water (200 mL), the solution was extracted with ethyl acetate (3×50 mL). The organic layers were collected, washed with brine (3×50 mL), dried and evaporated to furnish crude MC867, which was purified by chromatography on silica gel column (eluent: n-hexane/ethyl acetate/methanol 12/3/1).

[0135] Yield (%): 45; mp (° C.): 168-169; recrystallization solvent: cyclohexane; formula (molecula-weight): C₁₆H₁₆F₂N₂OS (322.37).

Example 2 2-Cyclopenlylthio-6-(2,6-difluorophenylmethyl)-3,4-dihydro-5-methylpyrimidin-4-(3H)-one (MC922)

[0136] The synthesis of MC922 was accomplished according to the above reported procedure starting from 6-(2,6-difluorophenylmethyl)-5-methyl-1,2,3,4-tetrahydro-2-thiopyrimidin-4-(3H)-one (see scheme B).

[0137] Yield (%): 54; mp (° C.): 192-193; recrystallization solvent: cyclohexane; formula (molecular weight): C₁₇H₁₈F₂N₂OS (336.40).

Example 3 2-Cyclopentylthio-6-{1-(2,6-difluorophenyl)ethyl}-3,4-dihydropyrimidin-4-(3H)-one (MC1008)

[0138] The synthesis of MC1008 was accomplished according to the above reported procedure starting from 6-{1-(2,6-difluorophenyl)ethyl}-1,2,3,4-tetrahydro-2-thiopyrimidin-4(3B)-one (see scheme B).

[0139] Yield (%): 54; mp (° C.): 165.5-166.5; recrystallization solvent: cyclohexane; formula (molecular weight): C₁₇H₁₈F₂N₂OS (336.40).

Example 4 2-Cyclopentylthio-6-{1-(2,6-difluorophenyl)ethyl}-3,4-dihydro-5-methylpyrimidin4(3H)-one (MC1047)

[0140] The synthesis of MC1047 was accomplished according to the above reported procedure, starting from 6-{1-(2,6-difluorophenyl)ethyl}-5-methyl-1,2,3,4-tetrahydro-2-thiopyrimidin-4(3H)-one (see scheme B).

[0141] Yield (%): 60; mp (° C.): 196-197; recrystallization solvent: cyclohexane; formula (molecular weight): C₁₈H₂₀F₂N₂OS (350.43).

Example 5 6-(2,6-Difluorophenylmethyl)-3,4-dihydro-2-(methylthiomethyl)thiopyrimidin-4-(3H)-one (MC1161)

[0142] The synthesis of MC1161 was accomplished according to the above reported procedures, starting from 6-(2,6-difluorophenylmethyl)-1,2,3,4-tetrahydro-2-thiopyrimidin-4(3H)-one (see scheme B) and chloromethyl methyl sulfide.

[0143] Yield (%): 72; mp (° C.): 159-160; recrystallization solvent: benzene/cyclohexane; formula (molecular weight): C₁₃H₁₂F₂N₂OS₂ (314.37).

Example 6 6-(2,6-Difluorophenylmethyl)-3,4-dihydro-5-methyl-2-(methylthiomethyl)thiopyrimidin-4(3H)-one (MC 1162)

[0144] The synthesis of MC1162 was accomplished according to the above reported procedure, starting from 6-(2,6-difluorophenylmethyl)-5-methyl-1,2,3,4-tetrahydro-2-thiopyrimidin 4(3H)-one (see scheme B) and chloromethyl methyl sulfide.

[0145] Yield (%): 70; mp (° C.): 183-184; recrystallization solvent: benzene/cyclohexane; formula (molecular weight): C₁₄H₁₄F₂N₂OS₂ (328.39).

Example 7 6-(2,6-Difluorophenylmethyl)-3,4-dihydro-5-(1-methylethyl)-2-(methylthiomethyl) thiopyrimidin-4-(3H)-one MC1145)

[0146] The synthesis of MC1145 was accomplished according to the above reported procedure, starting from 6-(2,6-difluorophenylmethyl)-5-(1-methylethyl)-1,2,3,4-tetrahydro-2-thiopyrimidin-4(3H)-one (see scheme B) and chloromethyl methyl sulfide.

[0147] Yield (%): 62; mp (° C.): 158.5-160; recrystallization solvent: cyclohexane; formula (molecular weight): C₁₆H₁₈F₂N₂OS₂ (356.45).

Example 8 2-Cyclopenltylamino-6-(2,6-difluorophenylmethyl)-3,4-dihydropyrimidin-4-(3H)-one (MC1022)

[0148] Cyclopentylamine (10 mL) was heated while stirring with 6-(2,6-difluorophenylmethyl)-3,4-dihydro-2-methylthiopyrimidin-4-(3H)-one (0.30 g, 1.12 mmol; prepared as reported in scheme B or C) in a sealed tube at 160° C. for 10 h. After cooling, the mixture was diluted with water (200 mL) and extracted with ethyl acetate (3×50 mL). The organic layers were collected, washed with brine (3×50 mL), dried and evaporated to furnish crude MC1022, which was purified by chromatography on silica get column (eluent: ethyl acetate/chloroform 1/1).

[0149] Yield (%): 74; mp (° C.): -(oil); formula (molecular weight): C₁₆H₁₇F₂N₃O (305.33).

Example 9 2-Cyclopentylamino-6-(2,6-difluorophenylmethyl)-3,4-dihydro-5-methylpyrimidin-4-(3H)-one (MC1050).

[0150] The synthesis of MC1050 was accomplished according to the above reported procedure, starting from 6-(2,6-difluorophenylmethyl)-3,4-dihydro-5-methyl-2-methylthiopyrimidirin-4(3H)-one (see scheme B or C).

[0151] Yield (%): 60; mp (° C.): 115-117; recrystallization solvent: n-hexane/cyclohexane; formula (molecular weight): C₁₇H₁₉F₂N₃O (319.35).

Example 10 2-Cyclopentylamino-6-{1-(2,6-difluorophenyl)ethyl}-3,4-dihydropyrimidin-4-(3H)-one (MC1048).

[0152] The synthesis of MC1048 was accomplished according to the above reported procedure, starting from 6-{1-(2,6-difluorophenyl)ethyl}-3,4-dihydro-2-methylthiopyrimidin-4(3H)-one (see scheme B or C).

[0153] Yield (%): 48; mp (° C.): -(oil); formula (molecular weight): C₁₇H₁₉F₂N₃O (319.35).

Example 11 2-Cyclopentylamino-6-{1-(2,6-difluorophenyl)ethyl}-3,4-dihydro-5-methylpyrimidin-4-(3H)-one (MC1129)

[0154] The synthesis of MC1129 was accomplished according to the above reported procedure, starting from 6-{1-(2,6-difluorophenyl)ethyl}-3,4-dihydro-5-methyl-2-methylthiopyrimidin-4(3H)-one (see scheme B or C).

[0155] Yield (%): 38; mp (° C.): -(oil); formula (molecular weight): C₁₈H₂₁F₂N₃O (333.38).

Example 12 6-(2,6-Difluorophenylmethyl)-3,4-dihydro-2-(4-thiomorpholin-1-yl)-pyrimidin-4-(3H)-one (MC1193)

[0156] The synthesis of MC1193 was accomplished according to the above reported procedure, starting from thiomorpholine and 6-(2,6-difluorophenylmethyl)-3,4-dihydro-2-methylthiopyrimidin-4(3H)-one (see scheme B or C).

[0157] Yield (%): 78; mp (° C.): 233-234; recrystallization solvent: acetonitrile; formula (molecular weight): C₁₅H₁₅F₂N₃OS (323.36).

Example 13 6-(2,6-Difluorophenylmethyl)-3,4-dihydro-2-N,N-dimethylaminopyrimidin-4-(3H)-one (MC1182)

[0158] To a stirred solution of sodium metal (0.14 g, 6.3 mg-atoms) in absolute ethanol (50 mL) 1,1-dimethylguanidine sulfate (1.17 g, 4.3 mmol) and ethyl 4-(2,6-difluorophenyl)acetylacetate (0.76 g, 3.15 mmol) were successively added. The mixture was heated while stirring at reflux for 8 h. After cooling, the solvent was distilled in vacuo at 40-50° C. until dryness and the residue was dissolved in water (200 mL) and made acid (pH 5) with 0.5N acetic acid. The resulting precipitate (the crude isocytosine derivative) was filtered under reduced pressure, washed with diethyl ether, vacuum dried at 80° C. for 12 h and then crystallized from benzene/cyclohexane (see scheme C starting from ethyl 4-(2,6-difluorophenyl)acetylacetate and replacing guanidine hydrochloride with 1,1-dimethylguanidine sulfate).

[0159] Yield (%): 88; mp (° C.): 210-211; recrystallization solvent: benzene/cyclohexane; formula (molecular weight): C₁₃H₁₃F₂N₃O (265.26).

Examples 14-16 Evaluation of Longevity of Protection from HIV

[0160] Compounds of the present invention were assayed for length of HIV protection using the following methods:

[0161] Cells.

[0162] To evaluate the antiviral activity of test compounds the following cell types were used: T lymphocytes (PBLs) and monocytes from peripheral blood of healthy donors; U937, human monocyte cell line permissive for HIV replication; C8166 and MT-4, human CD4⁺ T-cell lines permissive for HIV replication; H9, human CD4⁺ T-cell line permissive for HIV replication, but partially resistant to its cytopathic effect; H9/IIIB, subclone of H9 cells chronically infected with HIV-1 (strain IIIB). Cytotoxicity was evaluated in the above cell types and also in primary cultures of fibroblasts and in HeLa and ME-180 cell lines, which originated from human cervix. Cells were grown in RPMI-1640 (H9, MT-4, C8166, U937, PBMC, PBL) or in DMEM (HeLa, ME-180, fibroblasts) medium supplemented with 10% FCS, 100 units/mL penicillin and 100 μg/mL streptomycin. The cultures were incubated at 37° C. in a humidified, 5% CO₂ atmosphere. The absence of mycoplasma contamination was periodically checked by the Hoechst staining method.

[0163] Virus.

[0164] HIV-1(strains III_(B), NM, RF, Ba-L) and HIV-2 (ROD strain) were obtained from the supernatant of persistently infected cells. The CBL-20 strain of HIV-2, kindly obtained from “MRC AIDS Directed Program Reagent Project”, was propagated in MT-4 cells. Clinical isolates of HIV-1 from peripheral blood and from seminal fluid, were propagated in PBLs. The HIV stock solutions were titrated in C8166 cells and kept at −80° C. until use.

[0165] Cytotoxicity Assays.

[0166] Cells were resuspended in growth medium at a density of 1×10⁵/mL and incubated in the absence or in the presence of various concentrations of test compounds. Cell numbers at each concentration were determined in a Coulter counter after 72-96 hours at 37° C. The percentage of viable cells at each concentration was determined by the Trypan blue dye exclusion method or, alternatively, by the MTT method (see below).

[0167] P24 Assay.

[0168] The levels of p24 viral protein were determined in the cell-free culture supernatants by the HIV-1 p24 antigen enzyme-linked immunosorbent assay kit (ELISA, Abbott).

[0169] Evaluation of Long-Term Cytotoxicity.

[0170] MT-4 cells, seeded at 1×10⁵/mL in growth medium, were incubated in the absence or in the presence of various concentrations of the test compounds, alone or in combination. Every 3-4 days, in order to bring cells back to the initial conditions of low density and allow continuous exponential growth, the cultures were diluted in fresh medium containing or not the same concentrations of the test compounds. Cell viability was determined at each sub-cultivation stage by the MTT method.

[0171] MTT Method.

[0172] Due to easy execution and quick results, the colorimetric method based on the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide salt (MTT method) was used for the screening activity. Briefly, 50 μL of culture medium supplemented by 10% FCS and containing 1×10⁴ MT-4 cells was added to each well of flat bottomed microtitre trays containing 50 μL of medium with or without serial concentrations of the test compounds. 20 μL of a viral suspension was then added to give 100 CCID₅₀/well. After 4 days incubation at 37° C., the number of viable MT-4 cells was determined by the MTT method.

[0173] Evaluation of Long-Term Anti-HIV-1 Activity.

[0174] To evaluate the ability of compounds to extinguish the infection, the following experimental conditions were followed. 10⁶ MT-4 cells were infected at 20° C. for 1 hr with a very high virus load (up to 10 CCID₅₀/cell; 1 CCID₅₀=25-250 infectious virions), in the absence or in the presence of test compounds. At the end of infection, the cells were extensively washed and then resuspended in the absence or in the presence of test compounds at a density of 2×10⁵ cells/mL. 50 μL of the cell suspension, containing 1×10⁴ MT-4 cells, was added to each well of flat bottomed microtitre trays containing 50 μL of medium with or without serial dilution of the test compounds, alone or in combination. After 1 hour at 37° C. and at intervals during the successive 18 hours, sets of duplicate cultures were resuspended in the absence of the inhibitors and cultivated in drug-free medium thereafter (reverted cultures). After 4 days, surviving cultures were entirely sub-cultivated in fresh medium to bring cells back to initial density (2×10⁵ cells/mL) and allow exponential growth. The whole sample (0.1 mL) was resuspended in 0.9 mL of fresh medium containing the given drug concentrations and seeded in 24 multiwell plates. After 4 more days, the whole culture (1.0 mL) was resuspended in 9 mL of fresh medium (containing the given drug concentrations) in a 25-cm² flask. Starting at day 12, only one-tenth (in 25-cm² flasks) or one hundredth (in 24 multiwell plates) of each culture was further transplanted. For 4 weeks, at 4 days intervals, the anti-HIV activity of test compounds, alone and in combination, was evaluated by determining the following parameters: p24 levels; virus-induced cytopathogenicity; infectious virus yield; DNA and RNA viral sequences (by PCR).

[0175] It is worth noting that the above procedure, while providing conditions suitable for continuous exponential growth of the cultures, allowed all the cells which were originally infected (or the virus produced by them) to survive up to day 12 post infection (p.i.) and beyond.

[0176] Results

[0177]FIG. 1 is a three dimensional line graph showing the levels of viral p24 in cell culture supernatants treated with the specified concentrations of MC 1220. 10⁶ MT-4 cells were infected with a very high virus in the absence or in the presence of MC 1220. At the end of infection, the cells were extensively washed and then resuspended in the absence or in the presence of test compounds at a density of 2×10⁵ cells/mL. 50 μL of the cell suspension, containing 1×10⁴ MT-4 cells, was added to each well of flat bottomed microtitre trays containing 50 μL of medium with or without serial dilution of the MC 1220, alone or in combination. After 1 hour at 37° C. and at intervals during the successive 18 hours, sets of duplicate cultures were resuspended in the absence of the inhibitors and cultivated in drug-free medium thereafter (reverted cultures). After 4 days, surviving cultures were entirely sub-cultivated in fresh medium to bring cells back to initial density (2×10⁵ cells/mL) and allow exponential growth. The whole sample (0.1 mL) was resuspended in 0.9 mL of fresh medium containing the given drug concentrations and seeded in 24 multiwell plates. After 4 more days, the whole culture (1.0 mL) was resuspended in 9 mL of fresh medium (containing the given drug concentrations) in a 25-cm² flask. Starting at day 12, only one-tenth (in 25-cm² flasks) or one hundredth (in 24 multiwell plates) of each culture was further transplanted. For 4 weeks, at 4 days intervals, the anti-HIV activity of test compounds, alone and in combination, was evaluated by determining p24 levels. The levels of p24 viral protein were determined in the cell-free culture supernatants using the HIV-1 p24 antigen enzyme-linked immunosorbent assay kit (ELISA, Abbott). MC 1220 was able to maintain a sustained reduction of p24 in the culture supernatants at a concentration of 3.5 μM.

[0178]FIG. 2 is a three dimensional line graph showing the levels of viral p24 in cell culture supernatants treated with the specified concentrations of Nevirapine. Following the methods of FIG. 1, the levels of p24 viral protein were determined in the cell-free culture supernatants using the HIV-1 p24 antigen enzyme-linked immunosorbent assay kit (ELISA, Abbott). Culture supernatants were harvested at four day intervals, and the amount of p24 present in the supernatant was quantified. Nevirapine was able to maintain a sustained reduction of p24 in the culture supernatants at a concentration of 300 μM, approximately 86 fold higher than MC 1220.

[0179]FIG. 3 is a three dimensional line graph showing the levels of viral p24 in cell culture supernatants treated with the specified concentrations of MC-1047. Following the methods of FIG. 1, the levels of p24 viral protein were determined in the cell-free culture supernatants using the HIV-1 p24 antigen enzyme-linked immunosorbent assay kit (ELISA, Abbott). Culture supernatants were harvested at four day intervals, and the amount of p24 present in the supernatant was quantified. MC-1047 was able to maintain a sustained reduction of p24 in the culture supernatants at a concentration of 10 μM.

Example 17 Evaluation of Reverse Transcriptase Activity

[0180] Activity against RT can be evaluated in assays with enzymes obtained from partially purified high titer virus stocks prepared in MT-4 cells. Alternatively, recombinant RT (rRT) can be used. Assays with virion purified RT are performed at 37° for 30 min. in a 50 μL reaction mixture containing 50 mM Tris-HCl (pH 8.4), 1 mM dithiothreitol, 80 mM KCl, 6 mM MgCl₂, 0.5 mCi [³H]-dTTP (400 Ci/mmol), 0.05 OD₂₆₀ units/mL of Poly(rA)-oligo(dT)₁₀, 0.1% Triton x-100, test compounds and 0.006 units of enzyme. 40 μL aliquots are spotted on glass fiber filters (Whatman GF/A) and processed for determination of trichloroacetic acid-insoluble radioactivity. Assays with rRT, in the same reaction mixture contain [methyl-3H]-dTTP (46 Ci/mmol, ICN), or [1′,2′,3′-³H]-dGTP (42 Ci/mmol, ICN), 0.05 OD₂₆₀ units/mL of Poly(rA)-oligo(dT)₁₀ or Poly(rC)-oligo(dG)₁₂₋₁₈ (Pharmacia).

[0181] Formulations

[0182] The amount of DABO incorporated into the compositions of the present invention will depend upon the mode of administration, and the desired rate of release of the DABO. Because the composition acts topically, its final concentration will depend on the availability of the compound to bind HIV, in the particular composition employed. Generally speaking, a preferred dose of the composition will be in the range which delivers from about 50 to about 2500 mg, preferably from about 50 to about 1000 mg, and more generally from about 5 to about 5000 mg. The effective dosage range of the pharmaceutically acceptable salts and prodrugs can be calculated based on the weight of the parent drug to be delivered. If the salt or prodrug exhibits activity in itself, the effective dosage can be estimated as above using the weight of the salt or prodrug, or by other means known to those skilled in the art.

[0183] It is preferable to administer the active ingredient in conjunction with a pharmaceutically acceptable diluent or carrier, as a pharmaceutical formulation. The present invention thus also involves the use of a pharmaceutical formulation or composition comprising the active ingredient together with one or more pharmaceutically acceptable carriers or diluents and, optionally, other prophylactic ingredients. The carrier(s) or diluent(s) should be “acceptable” in the sense of being compatible with the other ingredients of the formulation and not deleterious to the recipient.

[0184] Pharmaceutical formulations include those suitable for vaginal, rectal or topical administration. The formulations may, where appropriate, be conveniently presented in discrete dosage units and may be prepared by any of the methods well known in the art of pharmacy. All such methods include the step of bringing into association the active ingredient with liquid carriers, gels or finely divided solid carriers or both and then, if necessary, shaping the product into the desired formulation.

[0185] Pharmaceutical formulations and preparations suitable for administration may conveniently be presented as a solution, an aqueous or oily suspension, or an emulsion. The active ingredient may also be presented as a bolus, electuary or paste. Liquid preparations for vaginal or rectal administration may contain conventional additives such as suspending agents, emulsifying agents, non-aqueous vehicles (which may include edible oils) or preservatives.

[0186] Pharmaceutical formulations suitable for rectal or vaginal administration, wherein the carrier is a solid, are most preferably represented as unit dose suppositories. Suitable carriers include cocoa butter and other materials commonly used in the art, and the suppositories may be conveniently formed by admixture of the active compound with the softened or melted carrier(s) followed by chilling and shaping in molds.

[0187] Although aqueous gel formulations (described in more detail below) are preferred for “stand-alone” compositions that are not packaged with condoms, anti-viral compositions that are packaged with condoms do not require gels. A lubricant composition packaged with a condom requires only a water-soluble lubricating agent, such as glycerin or propylene glycol. Other components, such as water and a thickening agent, may be added to a condom lubricant if desired.

[0188] For “stand-alone” lubricants (i.e. lubricants that are not pre-packaged with condoms), gels and similar aqueous formulations are generally preferred, for various reasons (both scientific and economic) known to those skilled in the art. While the carrier substance used in a particular lubricant is not critical to this invention, in a preferred embodiment the carrier fluid of a lubricant gel as disclosed herein comprises (a) water, (b) a thickening agent, and (c) a lubricating agent.

[0189] Preferred thickening agents include cellulose or a chemically treated derivative of cellulose. Derivatives of cellulose which have been chemically treated to make them more hydrophilic (such as hydroxyethyl and hydroxymethyl derivatives, which have numerous additional hydroxy groups bonded to the starting cellulose molecules) have been widely used as thickening agents in gels that are applied to the skin. Other suitable thickening agents include acacia, agar, alginate, carrageenan, gum tragacanth, xanthan gum, collagen, carboxypolymethylene, glyceryl monostearate, polyvinylpyrrolidone, and polyacrylamide. The thickening agents listed above are relatively inactive biologically, and basically serve as carrier substances.

[0190] As used herein, “lubricating agent” refers to a component which is incorporated into a genital lubricant for the purpose of reducing friction during intercourse. Although any liquid (including water) sometimes functions as a “lubricant” in the broadest sense of the word, four characteristics distinguish a preferred lubricating agent, for purposes hereof, from water and other liquids that do not have the characteristics preferred for effective and comfortable lubrication during sexual intercourse. A preferred lubricating agent: (1) is substantially more viscous than water and feels slippery when rubbed between two skin surfaces; (2) has an affinity for human skin, and when applied to skin, it spreads smoothly and evenly across the contacted area; (3) remains in contact with the skin, clinging to it in a more substantial manner than water, which is easily wiped away; and, (4) has a low level of volatility, and does not evaporate quickly or become sticky.

[0191] The foregoing characteristics can be easily recognized and understood, on a practical level, by rubbing a conventional lubricating agent (such as glycerin or mineral oil) between the fingers. The nature and the durability of the lubrication, and the differences between such agents and other liquids such as plain water, are readily apparent.

[0192] In addition, in order to be physiologically acceptable, preferred lubricating agents are gradually broken down into innocuous substances in the body (in cases in which they are absorbed by tissue to a significant degree through the skin or mucous membranes), or they are of a nature that allows them to be secreted by the vagina and washed cleanly from the skin. In either case, they do not foul or clog the pores in skin or mucous membranes, leave any unacceptable residues, or cause other adverse effects if used repeatedly over a span of months, during numerous acts of intercourse.

[0193] Several lubricating agents which are used in commercially available sexual lubricants satisfy these criteria, including glycerin (also called glycerine, glycerol, 1,2,3-propanetriol, and trihydroxypropane) and certain types of polyethylene glycol (PEG), such as PEG 200 or PEG 400 (the numbers indicate different molecular weight averages). Various other polymers (such as polypropylene glycol, polyisobutene, and polyoxyethylene) and certain naturally-occurring compounds (such as behenic acid, derived from various types of seeds and animal fats) and their derivatives (such as behenyl alcohol) are also used as lubricants in cosmetics and other formulations that contact the skin. In addition, some sugar-alcohols such as sorbitol, and some silicon compounds such as polydimethylsiloxane, are also used as skin-contacting lubricating agents.

[0194] Other components, including preservatives (such as chlorhexidine gluconate), anti-crystallization agents (such as glucono-delta-lactate), fragrances, coloring agents, alkaline or acidic or buffering agents to maintain the proper pH, and soothing or anti-swelling agents (such as lanolin, aloe vera extract, or hydrocortisone) can be added to the compositions described herein.

[0195] Various forms of packaging may be used for the articles of manufacture disclosed herein. By way of illustration, a variety of different packages are used for (i) condoms, which are usually packaged in sealed plastic or foil packages with a single condom in each sealed sterile package; and (ii) “stand-alone” lubricants.

[0196] In a preferred embodiment, a “stand-alone” lubricant is packaged, shipped, and handled in a package that renders it convenient and useful as a lubricant during intercourse. Types of packaging that are commonly used for stand-alone gels and similar formulations include:

[0197] (1) A watertight tube made of deformable metallic foil or plastic walls. Such tubes usually are sealed at one end by means such as crimping, and have an outlet orifice at an opposed second end, which can be covered and sealed by a removable and/or openable device such as a threaded or flip-top cap.

[0198] (2) A small, flat, watertight packet which contains a sufficient quantity of lubricant for a single use during intercourse (such as about 5 to 10 milliliters, or about 1 to 2 teaspoons). Such packets can be made of plastic, metallized foil, or other suitable material.

[0199] (3) A small single-dose container made of a breakable plastic or other material, which can be opened by breaking off a component that protrudes outwardly from the container, thereby unsealing an outlet orifice.

[0200] (4) A stiff-walled bottle, normally but not necessarily in an upright configuration, with a wall (typically cylindrical or with an elliptical or similar cross-sectional shape) made of plastic, glass, or other suitable material.

[0201] Another preferred embodiment of genital lubricants that contain an anti-viral composition involves condom lubricants. As used herein, “condom lubricant” refers to a fluidized substance that is spread across one or more surfaces of a condom, and which is contained within a sealed watertight package that contains a condom. In other words, “condom lubricant” refers to lubricants that are pre-packaged with condoms, and does not include “stand-alone” lubricants packaged without condoms, as described above.

[0202] This invention has been described with reference to its preferred embodiments. Variations and modifications of the invention will be obvious to those skilled in the art from the foregoing detailed description of the invention. 

What is claimed is: 1) A method for inhibiting sexual transmission of HIV comprising topically applying to the skin or epithelial tissue of a human an effective amount of a dihydro-alkyloxy-benzyl-oxopyrimidine of formula (A):

wherein: X is —O, —CH₂, —CHK¹ (wherein K¹ is —H, —C₁₋₄alkyl, —C₃₋₆Cycloalkyl), —S, —NK² (wherein K² is —H, —C₁₋₄alkyl, —C₃₋₆cycloalkyl, or a bond when X—R is nitro), -aryl, or -arylalkyl; R is —H, —C₁₋₄alkyl (optionally containing one or more of heteroatoms selected from O, S, and N), —C₃₋₆ cycloalkyl (optionally containing one or more of heteroatoms selected from O, S, N), -aryl, -arylakl, heterocycle, oxo, thio, or a primary amine; Y is —H, —C₁₋₄alkyl, or —C₃₋₆cycloalkyl; Z is —H, —C₁₋₄alkyl, or —C₃₋₁cycloalkyl; R₁ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, aryl), or —SW  (wherein W is —H, —CH₃, -aryl); R₂ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃, -aryl); R₃ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃, -aryl); R₄ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃,-aryl); and R₅ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl), or —SW (wherein W is —H, —CH₃, -aryl). 2) The method of claim 1 wherein the composition is applied to the vaginal endothelium, the rectal endothelium, or the male genetalia. 3) The method of claim 1 wherein the composition is in the form of a cream, lotion, gel, or foam. 4) The method of claim 1 wherein the composition is in the form of an intra-vaginal pill, an intra-rectal pill, or a suppository. 5) The method of claim 1 wherein the composition is topically applied by release from an intravaginal device selected from a vaginal ring, a vaginal sponge, a diaphram, or a cervical cap. 6) The method of claim 1 wherein the composition is topically applied from the exterior surface of a condom or vaginal applicator. 7) The method of claim 1 wherein the composition further comprises a second anti-HIV agent, a viruside effective against viral infections other than HIV, and/or a spermicide. 8) The method of claim 1 wherein the composition further comprises a lubricant. 9) The method of claim 1 wherein, in formula (A), Y is —C₁₋₄alkyl, and Z is —C₁₋₄alkyl. 10) The method of claim 1 wherein, in formula (A), R₁ and R₅ are halogen. 11) The method of claim 1 wherein, in formula (A), Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen. 12) The method of claim 1 wherein, in formula (A), —X—R is —N-Me₂, Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen. 13) The method of claim 1 wherein, in formula (A), —X—R is —NH-cPe, Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen. 14) The method of claim 1 wherein, in formula (A), —X—R is —N═O, Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen. 15) The method of claim 1 wherein, in formula (A), —X—R is —S-Me, Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen. 16) The method of claim 1 wherein, in formula (A), —X—R is —S-MeSMe, Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen. 17) A topical composition in the form of a cream, lotion, gel, or foam, comprising a dihydro-alkyloxy-benzyl-oxopyrimidine of formula (A):

wherein: X is —O, —CH₂, —CHK¹ (wherein K¹ is —H, —C₁₋₄ alkyl, —C₃₋₆Cycloalkyl), —S,—NK² (wherein K² is —H, —C₁₋₄alkyl, —C₃₋₆cycloalkyl, or a bond when X—R is nitro), -aryl, or -arylalkyl; R is —H, —C₁₋₄alkyl (optionally containing one or more of heteroatoms selected from O, S, and N), —C₃₋₆ cycloalkyl (optionally containing one or more of heteroatoms selected from O, S, N), -aryl, -arylakl, heterocycle, oxo, thio, or a primary amine; Y is —H, —C₁₋₄alkyl, or —C₃₋₆cycloalkyl; Z is —H, —C₁₋₄alkyl, or —C₃₋₆cycloalkyl; R₁ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, aryl), or —SW  (wherein W is —H, —CH₃, -aryl); R₂ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃, -aryl); R₃ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃, -aryl); R₄ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃,-aryl); and R₅ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl), or —SW (wherein W is —H, —CH₃, -aryl). 18) The composition of claim 17 further comprising a second anti-HIV agent. 19) The composition of claim 17 further comprising a viruside effective against viral infections other than HIV. 20) The composition of claim 17 further comprising a spermicide. 21) The composition of claim 17 further comprising a lubricant. 22) A composition in the form of an intra-vaginal or intra-rectal pill or suppository comprising a dihydro-alkyloxy-benzyl-oxopyrimidine of formula (A):

wherein: X is —O, —CH₂, —CHK¹ (wherein K¹ is —H, —C₁₋₄alkyl, —C₃₋₆Cycloalkyl), —S,—NK² (wherein K² is —H, —C₁₋₁alkyl, —C₃₋₆Cycloalkyl, or a bond when X—R is nitro), -aryl, or -arylalkyl; R is —H, —C₁₋₄alkyl (optionally containing one or more of heteroatoms selected from O, S, and N), —C₃₋₆ cycloalkyl (optionally containing one or more of heteroatoms selected from O, S, N), -aryl, -arylakl, heterocycle, oxo, thio, or a primary amine; Y is —H, —C₁₋₄alkyl, or —C₃₋₆cycloalkyl; Z is —H, —C₁₋₄alkyl, or —C₃₋₆cycloalkyl; R₁ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, aryl), or —SW  (wherein W is —H, —CH₃, -aryl); R₂ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃, -aryl); R₃ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃, -aryl); R₄ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃,-aryl); and R₅ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl), or —SW (wherein W is —H, —CH₃, -aryl). 23) The composition of claim 22 further comprising a second anti-HIV agent. 24) The composition of claim 22 further comprising a viruside effective against viral infections other than HIV. 25) The composition of claim 22 further comprising a spermicide. 26) A device for inhibiting the sexual transmission of HIV comprising: a) a barrier structure for insertion into the vaginal cavity, and b) a composition comprising a dihydro-alkyloxy-benzyl-oxopyrimidine of formula (A):

wherein: X is —O, —CH₂, —CHK¹ (wherein K¹ is —H, —C₁₋₄ alkyl, —C₃₋₆Cycloalkyl), —S, —NK² (wherein K² is —H, —C₁₋₄alkyl, —C₃₋₆cycloalkyl, or a bond when X—R is nitro), -aryl, or -arylalkyl; R is —H, —C₁₋₄alkyl (optionally containing one or more of heteroatoms selected from O, S, and N), —C₃₋₆ cycloalkyl (optionally containing one or more of heteroatoms selected from O, S, N), -aryl, -arylakl, heterocycle, oxo, thio, or a primary amine; Y is —H, —C₁₋₄alkyl, or —C₃₋₆cycloalkyl; Z is —H, —C₁₋₄alkyl, or —C₃₋₆cycloalkyl; R₁ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, aryl), or —SW  (wherein W is —H, —CH₃, -aryl); R₂ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃, -aryl); R₃ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃, -aryl); R₄ is —H, —C₁₋₄alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl); or —SW  (wherein W is —H, —CH₃,-aryl); and R₅ is —H, —C₁₋₄-alkyl, -halogen, —NO₂, —OW (wherein W is —H, —CH₃, -aryl), or —SW (wherein W is —H, —CH₃, -aryl). 27) The device of claim 26 wherein the barrier structure is a vaginal sponge, diaphram, cervical cap, or condom. 28) The device of claim 26 wherein the composition further comprises a second anti-HIV agent, a viruside effective against viral infections other than HIV, and/or a spermicide. 29) A compound of formula (A):

wherein: a) —X—R is —N-Me₂,Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen; b) —X—R is —N═O, Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen; or c) —X—R is —S-MeSMe, Y is methyl, Z is methyl, R₁ and R₅ are fluorine, and R₂, R₃, and R₄ are hydrogen. 